Mexican billionaire Carlos Slim attends a news conference in Mexico City, Mexico October 16, 2019. REUTERS/Luis Cortes 

Mexican billionaire Carlos Slim attends a news conference in Mexico City, Mexico October 16, 2019. REUTERS/Luis Cortes 

Mexican billionaire Carlos Slim speaks during a news conference in Mexico City, Mexico October 16, 2019. REUTERS/Luis Cortes 

Mexican billionaire Carlos Slim attends a news conference in Mexico City, Mexico October 16, 2019. REUTERS/Luis Cortes 

Mexican billionaire Carlos Slim arrives for a news conference in Mexico City, Mexico October 16, 2019. REUTERS/Luis Cortes 

Mexican billionaire Carlos Slim arrives for a news conference in Mexico City, Mexico October 16, 2019. REUTERS/Luis Cortes 

Carlos Slim Domit, Chairman of the Board of Directors of Grupo Carso, smiles during the opening ceremony of the Fundacion Telmex Mexico Siglo XXI (Telmex Foundation Mexico XXI Century) in Mexico City, Mexico, September 6, 2019. REUTERS/Edgard Garrido 

Carlos Slim Domit, Chairman of the Board of Directors of Grupo Carso, addresses the audience during the opening ceremony of the Fundacion Telmex Mexico Siglo XXI (Telmex Foundation Mexico XXI Century) in Mexico City, Mexico, September 6, 2019. REUTERS/Edgard Garrido 

Mexican tycoon Carlos Slim attends the opening ceremony of the Fundacion Telmex Mexico Siglo XXI (Telmex Foundation Mexico XXI Century) in Mexico City, Mexico, September 6, 2019. REUTERS/Edgard Garrido 

Mexican tycoon Carlos Slim attends the opening ceremony of the Fundacion Telmex Mexico Siglo XXI (Telmex Foundation Mexico XXI Century) in Mexico City, Mexico, September 6, 2019. REUTERS/Edgard Garrido 

Mexican tycoon Carlos Slim attends the opening ceremony of the Fundacion Telmex Mexico Siglo XXI (Telmex Foundation Mexico XXI Century) in Mexico City, Mexico, September 6, 2019. REUTERS/Edgard Garrido 

Mexican tycoon Carlos Slim arrives to listen to Mexico's President Andres Manuel Lopez Obrador during his first state of the union at National Palace in Mexico City, Mexico, September 1, 2019. REUTERS/Henry Romero 

Mexican tycoon Carlos Slim arrives to listen to Mexico's President Andres Manuel Lopez Obrador during his first state of the union at National Palace in Mexico City, Mexico, September 1, 2019. REUTERS/Henry Romero 

Mexican tycoon Carlos Slim arrives to listen to Mexico's President Andres Manuel Lopez Obrador during his first state of the union at National Palace in Mexico City, Mexico, September 1, 2019. REUTERS/Henry Romero 

Mexican tycoon Carlos Slim arrives to listen to Mexico's President Andres Manuel Lopez Obrador during his first state of the union at National Palace in Mexico City, Mexico, September 1, 2019. REUTERS/Henry Romero 

Mexican billionare Carlos Slim speaks in a joint news conference after the Competitive Advantage of Nations Forum in San Salvador, El Salvador, June 27, 2019. REUTERS/Jose Cabezas 

Mexican billionare Carlos Slim walks with President of El Salvador Nayib Bukele after the Competitive Advantage of Nations Forum in San Salvador, El Salvador, June 27, 2019. REUTERS/Jose Cabezas 

President of El Salvador Nayib Bukele participates in a joint news conference with billionaire Carlos Slim after the Competitive Advantage of Nations Forum in San Salvador, El Salvador, June 27, 2019. REUTERS/Jose Cabezas 

Mexican billionaire Carlos Slim and President of El Salvador Nayib Bukele participate in the Competitive Advantage of Nations Forum in San Salvador, El Salvador, June 27, 2019. REUTERS/Jose Cabezas 

President of El Salvador Nayib Bukele shakes hands with Mexican billionaire Carlos Slim during the Competitive Advantage of Nations Forum in San Salvador, El Salvador, June 27, 2019. REUTERS/Jose Cabezas 

Mexican billionaire Carlos Slim participates in the Competitive Advantage of Nations Forum in San Salvador, El Salvador, June 27, 2019. REUTERS/Jose Cabezas 

Mexican billionaire Carlos Slim delivers a keynote speech about his vision of Mexico City's downtown historical center in Mexico City, Mexico May 23, 2019. REUTERS/Edgard Garrido 

Mexican billionaire Carlos Slim arrives to deliver a keynote speech about his vision of Mexico City's downtown historical center in Mexico City, Mexico May 23, 2019. REUTERS/Edgard Garrido 

Mexican billionaire Carlos Slim delivers a keynote speech about his vision of Mexico City's downtown historical center in Mexico City, Mexico May 23, 2019. REUTERS/Edgard Garrido 

Mexican billionaire Carlos Slim arrives to deliver a keynote speech about his vision of Mexico City's downtown historical center in Mexico City, Mexico May 23, 2019. REUTERS/Edgard Garrido 

Mexican billionaire Carlos Slim delivers a keynote speech about his vision of Mexico City's downtown historical center in Mexico City, Mexico May 23, 2019. REUTERS/Edgard Garrido 

Mexican billionaire Carlos Slim arrives to deliver a keynote speech about his vision of Mexico City's downtown historical center in Mexico City, Mexico May 23, 2019. REUTERS/Edgard Garrido 

Mexican billionaire Carlos Slim delivers a keynote speech about his vision of Mexico City's downtown historical center in Mexico City, Mexico May 23, 2019. REUTERS/Edgard Garrido 

Mexican billionaire Carlos Slim arrives to deliver a keynote speech about his vision of Mexico City's downtown historical center in Mexico City, Mexico May 23, 2019. REUTERS/Edgard Garrido 

Mexican billionaire Carlos Slim arrives to deliver a keynote speech about his vision of Mexico City's downtown historical center in Mexico City, Mexico May 23, 2019. REUTERS/Edgard Garrido 

Mexican tycoon Carlos Slim attends the speech marking the first 100 days of the presidency of Mexico's President Andres Manuel Lopez Obrador at the National Palace in Mexico City, Mexico March 11, 2019. REUTERS/Edgard Garrido 

Tennis - ATP 500 - Acapulco Open, Acapulco, Mexico - March 2, 2019 Mexico's businessman Carlos Slim in the stands during the match REUTERS/Henry Romero 

Tennis - ATP 500 - Acapulco Open, Acapulco, Mexico - March 2, 2019 Mexico's businessman Carlos Slim in the stands during the match REUTERS/Henry Romero 

Mexican tycoon Carlos Slim arrives for the inauguration of Mexico's new President Andres Manuel Lopez Obrador, at the Congress in Mexico City, Mexico December 1, 2018. REUTERS/Henry Romero 

Mexican tycoon Carlos Slim arrives for the inauguration of Mexico's new President Andres Manuel Lopez Obrador, at the Congress in Mexico City, Mexico December 1, 2018. REUTERS/Henry Romero 

Mexico's President-elect Andres Manuel Lopez Obrador (L) shakes hands with Mexico's businessman Carlos Slim after giving his speech during a meeting with members of the Mexican association of engineers at the Palace of Mines in Mexico City, Mexico August 6, 2018. REUTERS/Henry Romero 

Mexico's businessman Carlos Slim leaves after a meeting with Mexico's President-elect Andres Manuel Lopez Obrador and the members of the Mexican association of engineers at the Palace of Mines in Mexico City, Mexico August 6, 2018. REUTERS/Henry Romero 

Mexican billionaire Carlos Slim attends the presentation of the Spanish building and services group FCC strategy plan in Madrid, Spain, July 31, 2018. REUTERS/Susana Vera 

Mexican billionaire Carlos Slim attends the presentation of the Spanish building and services group FCC strategy plan in Madrid, Spain, July 31, 2018. REUTERS/Susana Vera 

Mexican billionaire Carlos Slim and Esther Koplowitz, Deputy Chairman and second largest shareholder of the Spanish building and services group FCC, attend the presentation of the company's strategy plan in Madrid, Spain, July 31, 2018. REUTERS/Susana Vera 

Mexican billionaire Carlos Slim, Esther Koplowitz, Deputy Chairman and second largest shareholder of the Spanish building and services group FCC, and Esther Alcocer Koplowitz, Chairman of FCC, attend the presentation of the company's strategy plan in Madrid, Spain, July 31, 2018. REUTERS/Susana Vera 

Mexican billionaire Carlos Slim and Esther Koplowitz, Deputy Chairman and second largest shareholder of the Spanish building and services group FCC, attend the presentation of the company's strategy plan in Madrid, Spain, July 31, 2018. REUTERS/Susana Vera 

Mexican billionaire Carlos Slim speaks during the presentation of the Spanish building and services group FCC strategy plan in Madrid, Spain, July 31, 2018. REUTERS/Susana Vera 

Mexican billionaire Carlos Slim speaks during the presentation of the Spanish building and services group FCC strategy plan in Madrid, Spain, July 31, 2018. REUTERS/Susana Vera 

Mexican billionaire Carlos Slim looks on during a news conference in Mexico City, Mexico, April 16, 2018. REUTERS/Henry Romero 

Mexican billionaire Carlos Slim looks on during a news conference in Mexico City, Mexico, April 16, 2018. REUTERS/Henry Romero 

Mexican billionaire Carlos Slim looks on during a news conference in Mexico City, Mexico, April 16, 2018. REUTERS/Henry Romero 

Mexican billionaire Carlos Slim looks on during a news conference in Mexico City, Mexico, April 16, 2018. REUTERS/Henry Romero 

Mexican billionaire Carlos Slim looks on during a news conference in Mexico City, Mexico, April 16, 2018. REUTERS/Henry Romero 

Mexican billionaire Carlos Slim looks on during a news conference in Mexico City, Mexico, April 16, 2018. REUTERS/Henry Romero 

Mexican billionaire Carlos Slim speaks during a news conference in Mexico City, Mexico, April 16, 2018. REUTERS/Henry Romero 

Mexican billionaire Carlos Slim speaks during a news conference in Mexico City, Mexico, April 16, 2018. REUTERS/Henry Romero 

Mexican billionaire Carlos Slim speaks during a news conference in Mexico City, Mexico, April 16, 2018. REUTERS/Henry Romero 

Mexican billionaire Carlos Slim speaks during a news conference in Mexico City, Mexico, April 16, 2018. REUTERS/Henry Romero 

Mexican billionaire Carlos Slim speaks during a news conference in Mexico City, Mexico, April 16, 2018. REUTERS/Henry Romero 

Mexican billionaire Carlos Slim gestures during a news conference in Mexico City, Mexico, April 16, 2018. REUTERS/Henry Romero 

Mexican billionaire Carlos Slim speaks during a news conference in Mexico City, Mexico, April 16, 2018. REUTERS/Henry Romero 

Mexican billionaire Carlos Slim looks on during a news conference in Mexico City, Mexico, April 16, 2018. REUTERS/Henry Romero 

Chairman of the Board of Directors of Grupo Carso, Carlos Slim Domit, speaks to the media at America Movil's corporate offices in Mexico City, Mexico March 14, 2018. REUTERS/Carlos Jasso 

Chairman of the Board of Directors of Grupo Carso, Carlos Slim Domit, speaks to the media at America Movil's corporate offices in Mexico City, Mexico March 14, 2018. REUTERS/Carlos Jasso