Cuba announced Wednesday it will pull thousands of its doctors out of Brazil in response to President-elect Jair Bolsonaro's "direct, contemptuous and threatening" remarks about its medical aid program. The end of the "Mas Medicos," or "More Doctors," program signals a sharp deterioration in relations between communist Cuba and Brazil, which just elected far-right presidential candidate Jair Bolsonaro. He takes office Jan. 1.

Cuba made the announcement after Bolsonaro said the program overseen by the World Health Organization could only continue if doctors directly received their salaries from Brazil, and were able to bring their families with them during their assignments, among other conditions. The Cuban government generally keeps most of the salaries of state employees working abroad as part of the socialist state's "international missions." Participants also are generally barred from bringing family members in a measure that critics say is designed to prevent doctors from emigrating. "Mas Medicos" started five years ago under leftist President Dilma Rousseff. Cuba said roughly 20,000 doctors saw millions of patients in areas such as the Amazon rainforest and slums of major cities.

Bolsonaro said that he will grant asylum to any Cuban national who asks for it, escalating tensions with the Caribbean island after it ended the medical program. Far-right legislator Bolsonaro described the Cuban medical program as "slave labor," as doctors based in Brazil do not keep all of their salaries, with much of the crucial foreign income going to the Cuban government. Bolsonaro added that Cuba's decision to pull the program was unilateral.

Cuba's "white-coat diplomacy" was begun under Fidel Castro after the 1959 revolution, and has grown to become the island's most valuable export, bringing in an estimated $11 billion a year. Cuban media reported this week that Havana is sending 500 more doctors to crisis-wracked Venezuela.