A woman, wearing a protective mask, lays flowers during the celebrations of Victory Day, which marks the anniversary of the victory over Nazi Germany in World War Two, amid the outbreak of the coronavirus disease (COVID-19) in Sofia, Bulgaria, May 9, 2020. REUTERS/Stoyan Nenov

Women sing songs during the celebrations of Victory Day, which marks the anniversary of the victory over Nazi Germany in World War Two, amid the outbreak of the coronavirus disease (COVID-19) in Sofia, Bulgaria, May 9, 2020. REUTERS/Stoyan Nenov

A man, wearing a protective mask, walks after laying flowers during the celebrations of Victory Day, which marks the anniversary of the victory over Nazi Germany in World War Two, amid the outbreak of the coronavirus disease (COVID-19) in Sofia, Bulgaria, May 9, 2020. REUTERS/Stoyan Nenov

A man, wearing a t-shirt with a portrait of Russian President Vladimir Putin attends the celebrations of Victory Day, which marks the anniversary of the victory over Nazi Germany in World War Two, amid the outbreak of the coronavirus disease (COVID-19) in Sofia, Bulgaria, May 9, 2020. REUTERS/Stoyan Nenov

A man, wearing a protective mask, attends the celebrations of Victory Day, which marks the anniversary of the victory over Nazi Germany in World War Two, amid the outbreak of the coronavirus disease (COVID-19) in Sofia, Bulgaria, May 9, 2020. REUTERS/Stoyan Nenov

A man, wearing a protective mask, holds a portrait of Soviet leader Joseph Stalin during the celebrations of Victory Day, which marks the anniversary of the victory over Nazi Germany in World War Two, amid the outbreak of the coronavirus disease (COVID-19) in Sofia, Bulgaria, May 9, 2020. REUTERS/Stoyan Nenov

A man, wearing a protective mask, holds a portrait of Soviet leader Joseph Stalin during the celebrations of Victory Day, which marks the anniversary of the victory over Nazi Germany in World War Two, amid the outbreak of the coronavirus disease (COVID-19) in Sofia, Bulgaria, May 9, 2020. REUTERS/Stoyan Nenov

Bulgarian army special forces soldiers take part in a demonstration to mark the Bravery Day, as the annual military parade was canceled in an effort to prevent the spread of the coronavirus disease (COVID-19), at Tsrantcha military training field, Bulgaria May 6, 2020. REUTERS/Stoyan Nenov

Bulgarian army special forces soldiers take part in a demonstration to mark the Bravery Day, as the annual military parade was canceled in an effort to prevent the spread of the coronavirus disease (COVID-19), at Tsrantcha military training field, Bulgaria May 6, 2020. REUTERS/Stoyan Nenov

Bulgarian army special forces soldiers take part in a demonstration to mark the Bravery Day, as the annual military parade was canceled in an effort to prevent the spread of the coronavirus disease (COVID-19), at Tsrantcha military training field, Bulgaria May 6, 2020. REUTERS/Stoyan Nenov

Bulgarian army special forces soldiers take part in a demonstration to mark the Bravery Day, as the annual military parade was canceled in an effort to prevent the spread of the coronavirus disease (COVID-19), at Tsrantcha military training field, Bulgaria May 6, 2020. REUTERS/Stoyan Nenov

Bulgarian army special forces soldiers prepare for a demonstration to mark the Bravery Day, as the annual military parade was canceled in an effort to prevent the spread of the coronavirus disease (COVID-19), at Tsrantcha military training field, Bulgaria May 6, 2020. REUTERS/Stoyan Nenov

Bulgarian army special forces soldiers prepare for a demonstration to mark the Bravery Day, as the annual military parade was canceled in an effort to prevent the spread of the coronavirus disease (COVID-19), at Tsrantcha military training field, Bulgaria May 6, 2020. REUTERS/Stoyan Nenov

Bulgarian Patriarch Neophyte leads the Palm Sunday service in Alexander Nevski cathedral in Sofia, Bulgaria, April 12, 2020. REUTERS/Stoyan Nenov

Veselin Mareshki, leader of Bulgarian party Volya (Will), and a deputy from his party wear protective suits during debates in the parliament in Sofia, Bulgaria, March 20, 2020. REUTERS/Dimitar Kyosemarliev TPX IMAGES OF THE DAY

Veselin Mareshki, leader of Bulgarian party Volya (Will), walks in a protective suit during debates in the parliament in Sofia, Bulgaria, March 20, 2020. REUTERS/Dimitar Kyosemarliev

Workers in protective suits arrive to disinfect St. Stefan Bulgarian Orthodox Church in Istanbul,Turkey March 17, 2020. REUTERS/Umit Bektas

Workers in protective suits disinfect St. Stefan Bulgarian Orthodox Church in Istanbul,Turkey March 17, 2020. REUTERS/Umit Bektas

Workers in protective suits disinfect St. Stefan Bulgarian Orthodox Church in Istanbul,Turkey March 17, 2020. REUTERS/Umit Bektas

Workers in protective suits disinfect St. Stefan Bulgarian Orthodox Church in Istanbul,Turkey March 17, 2020. REUTERS/Umit Bektas

A worker in protective suit disinfects St. Stefan Bulgarian Orthodox Church in Istanbul,Turkey March 17, 2020. REUTERS/Umit Bektas

Workers in protective suits disinfect St. Stefan Bulgarian Orthodox Church in Istanbul,Turkey March 17, 2020. REUTERS/Umit Bektas

A worker in protective suit disinfects St. Stefan Bulgarian Orthodox Church in Istanbul,Turkey March 17, 2020. REUTERS/Umit Bektas

Workers in protective suits disinfect St. Stefan Bulgarian Orthodox Church in Istanbul,Turkey March 17, 2020. REUTERS/Umit Bektas

A worker in protective suit disinfects St. Stefan Bulgarian Orthodox Church in Istanbul,Turkey March 17, 2020. REUTERS/Umit Bektas

Workers in protective suits disinfect St. Stefan Bulgarian Orthodox Church in Istanbul,Turkey March 17, 2020. REUTERS/Umit Bektas

A worker in protective suit disinfects St. Stefan Bulgarian Orthodox Church in Istanbul,Turkey March 17, 2020. REUTERS/Umit Bektas

A Bulgarian public bus driver works behind restriction lines in Sofia after the Sofia Municipality imposed measures to curb the spread of coronavirus, in Sofia, Bulgaria March 13, 2020. REUTERS/Dimitar Kyosemarliev

Two Bulgarian women wearing protective masks are seen in Sofia downtown, Bulgaria March 13, 2020. REUTERS/Dimitar Kyosemarliev

European Council President Charles Michel speaks during a news conference with EU Commission President Ursula von der Leyen and Bulgarian Prime Minister Boyko Borissov in Sofia, Bulgaria, March 3, 2020. REUTERS/Dimitar Kyosemarliev

EU Commission President Ursula von der Leyen speaks during a news conference with Bulgarian Prime Minister Boyko Borissov and and European Council President Charles Michel (R) in Sofia, Bulgaria, March 3, 2020. REUTERS/Dimitar Kyosemarliev

EU Commission President Ursula von der Leyen speaks during a news conference with Bulgarian Prime Minister Boyko Borissov in Sofia, Bulgaria, March 3, 2020. REUTERS/Dimitar Kyosemarliev

People walk at the Bulgarian side of the "Kapitan Andreevo Border Crossing" with Turkey, March 2, 2020. REUTERS/Florion Goga

Bulgarian and EU flags flutter at the Bulgarian side of the "Kapitan Andreevo Border Crossing" with Turkey, March 2, 2020. REUTERS/Florion Goga

Border police officers wearing face masks and a police dog stand amid trucks at the Bulgarian side of the "Kapitan Andreevo Border Crossing" with Turkey, March 2, 2020. REUTERS/Florion Goga

Border police officers wearing face masks and a police dog inspect a truck at the Bulgarian side of the "Kapitan Andreevo Border Crossing" with Turkey, March 2, 2020. REUTERS/Florion Goga

A border police officer wearing a face masks uses a dog to inspect a truck at the Bulgarian side of the "Kapitan Andreevo Border Crossing" with Turkey, March 2, 2020. REUTERS/Florion Goga

Bulgarian Greco-Roman wrestler Edmond "Eddie" Nazaryan, 18, poses for a picture in Sofia, Bulgaria, February 26, 2020. Picture taken February 26, 2020. REUTERS/Stoyan Nenov

Bulgarian Greco-Roman wrestler Edmond "Eddie" Nazaryan, 18, prepares for his training in Sofia, Bulgaria, February 26, 2020. Picture taken February 26, 2020. REUTERS/Stoyan Nenov

Bulgarian Greco-Roman wrestler Edmond "Eddie" Nazaryan, 18, trains with his father Armen Nazaryan in Sofia, Bulgaria, February 26, 2020. Picture taken February 26, 2020. REUTERS/Stoyan Nenov

Bulgarian Greco-Roman wrestler Edmond "Eddie" Nazaryan, 18, trains with his father Armen Nazaryan in Sofia, Bulgaria, February 26, 2020. Picture taken February 26, 2020. REUTERS/Stoyan Nenov

A Bulgarian Muslim man carries his son on a horse as they attend a ritual ahead of a mass circumcision ceremony in the village of Ribnovo, Bulgaria, February 23, 2020. REUTERS/Stoyan Nenov TPX IMAGES OF THE DAY

A Bulgarian Muslim man carries his son on a horse as they attend a ritual ahead of a mass circumcision ceremony in the village of Ribnovo, Bulgaria, February 23, 2020. REUTERS/Stoyan Nenov

Bulgarian Muslim men demonstrate oil wrestling during a ritual ahead of a mass circumcision ceremony in the village of Ribnovo, Bulgaria, February 23, 2020. REUTERS/Stoyan Nenov

A Bulgarian Muslim man carries his son on a horse as they attend a ritual ahead of a mass circumcision ceremony in the village of Ribnovo, Bulgaria, February 23, 2020. REUTERS/Stoyan Nenov

A Bulgarian Muslim man carries his son on a horse as they attend a ritual ahead of a mass circumcision ceremony in the village of Ribnovo, Bulgaria, February 23, 2020. REUTERS/Stoyan Nenov

A Bulgarian Muslim man carries his son on a horse as they attend a ritual ahead of a mass circumcision ceremony in the village of Ribnovo, Bulgaria, February 23, 2020. REUTERS/Stoyan Nenov

A Bulgarian Muslim man carries his son on a horse as they attend a ritual ahead of a mass circumcision ceremony in the village of Ribnovo, Bulgaria, February 23, 2020. REUTERS/Stoyan Nenov

A Bulgarian Muslim man carries his son on a horse as they attend a ritual ahead of a mass circumcision ceremony in the village of Ribnovo, Bulgaria, February 23, 2020. REUTERS/Stoyan Nenov

Bulgarian Prime Minister Boyko Borissov leaves the second day of the European Union leaders summit, held to discuss the EU's long-term budget for 2021-2027, in Brussels, Belgium, February 21, 2020. REUTERS/Francois Lenoir

France's President Emmanuel Macron, German Chancellor Angela Merkel, Spain's Prime Minister Pedro Sanchez, Poland's Prime Minister Mateusz Morawiecki and Bulgarian Prime Minister Boyko Borissov attend the second day of the European Union leaders summit, held to discuss the EU's long-term budget for 2021-2027, in Brussels, Belgium, February 21, 2020. REUTERS/Yves Herman/Pool

France's President Emmanuel Macron, German Chancellor Angela Merkel, Spain's Prime Minister Pedro Sanchez, Poland's Prime Minister Mateusz Morawiecki and Bulgarian Prime Minister Boyko Borissov attend the second day of the European Union leaders summit, held to discuss the EU's long-term budget for 2021-2027, in Brussels, Belgium, February 21, 2020. REUTERS/Yves Herman/Pool

France's President Emmanuel Macron, Poland's Prime Minister Mateusz Morawiecki, Bulgarian Prime Minister Boyko Borissov and European Commission President Ursula von der Leyen attend the second day of the European Union leaders summit, held to discuss the EU's long-term budget for 2021-2027, in Brussels, Belgium, February 21, 2020. REUTERS/Yves Herman/Pool

France's President Emmanuel Macron, Poland's Prime Minister Mateusz Morawiecki, Bulgarian Prime Minister Boyko Borissov and European Commission President Ursula von der Leyen attend the second day of the European Union leaders summit, held to discuss the EU's long-term budget for 2021-2027, in Brussels, Belgium, February 21, 2020. REUTERS/Yves Herman/Pool

France's President Emmanuel Macron, Poland's Prime Minister Mateusz Morawiecki, Bulgarian Prime Minister Boyko Borissov and European Commission President Ursula von der Leyen attend the second day of the European Union leaders summit, held to discuss the EU's long-term budget for 2021-2027, in Brussels, Belgium, February 21, 2020. REUTERS/Yves Herman/Pool

Bulgarian Prime Minister Boyko Borissov reacts as he arrives for the second day of the European Union leaders summit, held to discuss the EU's long-term budget for 2021-2027, in Brussels, Belgium, February 21, 2020. REUTERS/Reinhard Krause

Bulgarian Prime Minister Boyko Borissov arrives for the second day of the European Union leaders summit, held to discuss the EU's long-term budget for 2021-2027, in Brussels, Belgium, February 21, 2020. REUTERS/Reinhard Krause

Bulgarian Prime Minister Boyko Borissov gestures as he arrives for the second day of the European Union leaders summit, held to discuss the EU's long-term budget for 2021-2027, in Brussels, Belgium, February 21, 2020. REUTERS/Reinhard Krause

Bulgarian Prime Minister Boyko Borissov arrives for the a special European council on budget in Brussels, Belgium February 20, 2020. Julien Warnand/Pool via REUTERS

German Chancellor Angela Merkel embraces with Bulgarian Prime Minister Boyko Borissov during the European Union leaders summit in Brussels, Belgium, February 20, 2020. REUTERS/Reinhard Krause