Slovakian Army T-72 tank of NATO enhanced Forward Presence battle group attends live shooting training during exercise Steele Crescendo as the coronavirus disease (COVID-19) continues in Adazi, Latvia May 8, 2020. REUTERS/Ints Kalnins

Spanish Army Leopard 2 and Slovakian Army T-72 tanks of NATO enhanced Forward Presence battle group attend live shooting training during exercise Steele Crescendo as the coronavirus disease (COVID-19) continues in Adazi, Latvia May 8, 2020. REUTERS/Ints Kalnins

Latvian and Slovakian soldiers attend a medical evacuation exercise during NATO military drill Crystal Arrow 2020 in Adazi, Latvia March 9, 2020. REUTERS/Ints Kalnins

Peter Pellegrini, election leader of Smer party, and former Slovakian President Andrej Kiska, leader of the For the People party, talk before a televised debate ahead of the country's parliamentary election in Bratislava, Slovakia, February 20, 2020. REUTERS/David W Cerny

Slovakian President Zuzana Caputova arrives for a reception at Downing Street hosted by Britian's Prime Minister Boris Johnson, ahead of the NATO summit in Watford, in London, Britain, December 3, 2019. Alastair Grant/Pool via REUTERS

British Prime Minister Boris Johnson and Slovakian Prime Minister Peter Pellegrini attend a round table meeting at the European Union leaders summit, in Brussels, Belgium October 17, 2019. Olivier Matthys/Pool via REUTERS

Slovakia's Interior Minister Denisa Sakova greets Slovakian soldiers at the end of the weekly general audience at the Vatican, September 11, 2019. REUTERS/Remo Casilli

French President Emmanuel Macron attends a meeting with his Slovakian counterpart Zuzana Caputova at the Elysee Presidential palace, in Paris, France July 24, 2019. Ludovic Marin/Pool via REUTERS

French President Emmanuel Macron attends a meeting with his Slovakian counterpart Zuzana Caputova at the Elysee Presidential palace, in Paris, France July 24, 2019. Ludovic Marin/Pool via REUTERS

Russian President Vladimir Putin, and Slovakian Prime Minister Peter Pellegrini, speak during their meeting at the St. Petersburg International Economic Forum (SPIEF 2019) in St. Petersburg, Russia June 6, 2019. REUTERS/Dmitri Lovetsky

Slovakian Prime Minister Peter Pellegrini speaks during his meeting with Russian President Vladimir Putin at the St. Petersburg International Economic Forum (SPIEF 2019) in St. Petersburg, Russia June 6, 2019. REUTERS/Dmitri Lovetsky

Russian President Vladimir Putin, speaks during his meeting with Slovakian Prime Minister Peter Pellegrini at the St. Petersburg International Economic Forum (SPIEF 2019) in St. Petersburg, Russia June 6, 2019. REUTERS/Dmitri Lovetsky

Russian President Vladimir Putin, welcomes Slovakian Prime Minister Peter Pellegrini during their meeting at the St. Petersburg International Economic Forum (SPIEF 2019) in St. Petersburg, Russia June 6, 2019. REUTERS/Dmitri Lovetsky

Russian President Vladimir Putin, and Slovakian Prime Minister Peter Pellegrini shake hands during their meeting at the St. Petersburg International Economic Forum (SPIEF 2019) in St. Petersburg, Russia June 6, 2019. REUTERS/Dmitri Lovetsky

Russian President Vladimir Putin, and Slovakian Prime Minister Peter Pellegrini shake hands during their meeting at the St. Petersburg International Economic Forum (SPIEF 2019) in St. Petersburg, Russia June 6, 2019. REUTERS/Dmitri Lovetsky

Russian President Vladimir Putin, and Slovakian Prime Minister Peter Pellegrini shake hands during their meeting at the St. Petersburg International Economic Forum (SPIEF 2019) in St. Petersburg, Russia June 6, 2019. REUTERS/Dmitri Lovetsky

Boris Kollar, leader of Slovakian party Sme Rodina (We Are Family) addresses a major rally of European nationalist and far-right parties ahead of EU parliamentary elections in Milan, Italy May 18, 2019. REUTERS/Alessandro Garofalo

Slovakian Prime Minister Peter Pellegrini arrives at a European Union emergency summit on Brexit in Brussels, Belgium, April 10, 2019. Alastair Grant/Pool via REUTERS

People walk past an election poster of Slovakian presidential candidate Zuzana Caputova in Bratislava, Slovakia, March 15, 2019. The poster reads: "President for fair Slovakia. Stand up against evil, together we can do it". REUTERS/David W Cerny

A woman walks past election posters of Slovakian presidential candidates Zuzana Caputova (L) and Bela Bugar in Bratislava, Slovakia, March 15, 2019. Posters read: "President for fair Slovakia. Stand up against evil, together we can do it" and "Vote for Bela Bugar". REUTERS/David W Cerny

Pedestrians walk past an election billboard poster of Zuzana Caputova, Slovakian presidential candidate, in Bratislava, Slovakia, March 4, 2019. The poster reads, "Zuzanna Caputova, my president. President for fair Slovakia. Stand up against evil, together we can do it". REUTERS/Radovan Stoklasa

A pedestrian walks past an election billboard poster of Zuzana Caputova, Slovakian presidential candidate, in Bratislava, Slovakia, March 4, 2019. The poster reads, "Zuzanna Caputova, my president. President for fair Slovakia. Stand up against evil, together we can do it". REUTERS/Radovan Stoklasa

An election billboard poster of Zuzana Caputova, Slovakian presidential candidate, is seen in Bratislava, Slovakia March 4, 2019. The poster reads, "Zuzanna Caputova, my president. President for fair Slovakia. Stand up against evil, together we can do it". REUTERS/Radovan Stoklasa

Zuzana Caputova, Slovakian presidential candidate, is seen on a screen of video camera during an interview with Reuters in Bratislava, Slovakia March 4, 2019. REUTERS/Radovan Stoklasa

Zuzana Caputova, Slovakian presidential candidate, poses for a photograph during an interview with Reuters in Bratislava, Slovakia March 4, 2019. REUTERS/Radovan Stoklasa

Zuzana Caputova, Slovakian presidential candidate, poses for a photograph during an interview with Reuters in Bratislava, Slovakia March 4, 2019. REUTERS/Radovan Stoklasa

Zuzana Caputova, Slovakian presidential candidate, attends an interview with Reuters in Bratislava, Slovakia March 4, 2019. REUTERS/Radovan Stoklasa

Zuzana Caputova, Slovakian presidential candidate, attends an interview with Reuters in Bratislava, Slovakia March 4, 2019. REUTERS/Radovan Stoklasa

Zuzana Caputova, Slovakian presidential candidate, gestures as she speaks during an interview with Reuters in Bratislava, Slovakia March 4, 2019. REUTERS/Radovan Stoklasa

Zuzana Caputova, Slovakian presidential candidate, speaks during an interview with Reuters in Bratislava, Slovakia March 4, 2019. REUTERS/Radovan Stoklasa

Zuzana Caputova, Slovakian presidential candidate, speaks during an interview with Reuters in Bratislava, Slovakia March 4, 2019. REUTERS/Radovan Stoklasa

Zuzana Caputova, Slovakian presidential candidate, speaks during an interview with Reuters in Bratislava, Slovakia March 4, 2019. REUTERS/Radovan Stoklasa

Poland's President Andrzej Duda speaks next to his Slovakian counterpart Andrej Kiska during a summit of eastern NATO countries in Kosice, Slovakia, February 28, 2019. REUTERS/David W Cerny

NATO Secretary General Jens Stoltenberg is welcomed by Slovakian President Andrej Kiska as he arrives at a summit of eastern NATO countries in Kosice, Slovakia February 28, 2019. REUTERS/David W Cerny

NATO Secretary General Jens Stoltenberg is welcomed by Slovakian President Andrej Kiska as he arrives at a summit of eastern NATO countries in Kosice, Slovakia February 28, 2019. REUTERS/David W Cerny

Hungary's President Janos Ader is welcomed by Slovakian President Andrej Kiska as he arrives at a summit of eastern NATO countries in Kosice, Slovakia February 28, 2019. REUTERS/David W Cerny

NATO Secretary General Jens Stoltenberg is welcomed by Slovakian President Andrej Kiska as he arrives at a summit of eastern NATO countries in Kosice, Slovakia February 28, 2019. REUTERS/David W Cerny

Estonian President Kersti Kaljulaid is welcomed by Slovakian President Andrej Kiska as she arrives at a summit of eastern NATO countries in Kosice, Slovakia February 28, 2019. REUTERS/David W Cerny

Estonian President Kersti Kaljulaid is welcomed by Slovakian President Andrej Kiska as she arrives at a summit of eastern NATO countries in Kosice, Slovakia February 28, 2019. REUTERS/David W Cerny

Estonian President Kersti Kaljulaid is welcomed by Slovakian President Andrej Kiska as she arrives at a summit of eastern NATO countries in Kosice, Slovakia February 28, 2019. REUTERS/David W Cerny

Romanian President Klaus Iohannis is welcomed by Slovakian President Andrej Kiska as he arrives at a summit of eastern NATO countries in Kosice, Slovakia February 28, 2019. REUTERS/David W Cerny

Poland's President Andrzej Duda is welcomed by Slovakian President Andrej Kiska as he arrives at a summit of eastern NATO countries in Kosice, Slovakia February 28, 2019. REUTERS/David W Cerny

Poland's President Andrzej Duda is welcomed by Slovakian President Andrej Kiska as he arrives at a summit of eastern NATO countries in Kosice, Slovakia February 28, 2019. REUTERS/David W Cerny

Poland's President Andrzej Duda is welcomed by Slovakian President Andrej Kiska as he arrives at a summit of eastern NATO countries in Kosice, Slovakia February 28, 2019. REUTERS/David W Cerny

Lithuanian President Dalia Grybauskaite is welcomed by Slovakian President Andrej Kiska as she arrives at a summit of eastern NATO countries in Kosice, Slovakia February 28, 2019. REUTERS/David W Cerny

Czech President Milos Zeman is welcomed by Slovakian President Andrej Kiska as he arrives at a summit of eastern NATO countries in Kosice, Slovakia February 28, 2019. REUTERS/David W Cerny

Latvian President Raimonds Vejonis is welcomed by Slovakian President Andrej Kiska as he arrives at a summit of eastern NATO countries in Kosice, Slovakia February 28, 2019. REUTERS/David W Cerny

Bulgarian President Rumen Radev is welcomed by Slovakian President Andrej Kiska as he arrives at a summit of eastern NATO countries in Kosice, Slovakia February 28, 2019. REUTERS/David W Cerny

Latvian President Raimonds Vejonis is welcomed by Slovakian President Andrej Kiska as he arrives at a summit of eastern NATO countries in Kosice, Slovakia February 28, 2019. REUTERS/David W Cerny

NATO Secretary General Jens Stoltenberg is welcomed by Slovakian President Andrej Kiska as he arrives at a summit of eastern NATO countries in Kosice, Slovakia February 28, 2019. REUTERS/David W Cerny

Slovakian President Andrej Kiska arrives at a summit of eastern NATO countries in Kosice, Slovakia February 28, 2019. REUTERS/David W Cerny

Slovakian army soldiers attend the NATO enhanced Forward Presence battle group military drill Integrated Capstone Exercise 2019/1 in Adazi, Latvia February 26, 2019. REUTERS/Ints Kalnins

Slovakian army soldiers attend the NATO enhanced Forward Presence battle group military drill Integrated Capstone Exercise 2019/1 in Adazi, Latvia February 26, 2019. REUTERS/Ints Kalnins

A child holds a Slovakian flag by a memorial on the first anniversary of the murder of the investigative reporter Jan Kuciak and his fiancee Martina Kusnirova in Bratislava, Slovakia, February 21, 2019. REUTERS/David W. Cerny

Slovakian President Andrej Kiska speaks during a news conference in Riga, Latvia December 18, 2018. REUTERS/Ints Kalnins

Slovakian President Andrej Kiska speaks during a news conference in Riga, Latvia December 18, 2018. REUTERS/Ints Kalnins

Slovakian President Andrej Kiska listens during a news conference in Riga, Latvia December 18, 2018. REUTERS/Ints Kalnins

Slovakian President Andrej Kiska listens during a news conference in Riga, Latvia December 18, 2018. REUTERS/Ints Kalnins

Latvian President Raimonds Vejonis and Slovakian President Andrej Kiska attend welcome ceremony in Riga, Latvia December 18, 2018. REUTERS/Ints Kalnins

Latvian President Raimonds Vejonis and Slovakian President Andrej Kiska attend welcome ceremony in Riga, Latvia December 18, 2018. REUTERS/Ints Kalnins