HAVANA — Cuba on Thursday accused the Trump administration of unfairly denying visas to diplomats assigned to work at the Cuban Embassy in Washington, which Cuban officials called part of a broader move to undo former President Barack Obama’s opening with the island.

Johana Tablada, Cuba’s deputy head of U.S. affairs, told The Associated Press that “after two decades of Cuba never denying a visa to the United States, the United States has stopped replying to multiple requests for visas for our personnel, who work in the United States to improve U.S-Cuba relations and attend to Cuban emigres and businesspeople who want to visit us.”

The Cuban Foreign Ministry said the U.S. has denied six visas to Cuban diplomats and approved 26 since September 2017. For its part, Cuba said, it approved 105 temporary and permanent visas for staff assigned to the U.S. Embassy in Havana. It said it denied only one, as a response to the U.S. actions.

Neither Cuban nor U.S. officials would say how many diplomats they currently have in each other’s countries.

Relations have soured dramatically since President Donald Trump took office promising to undo Obama’s detente with Cuba. The U.S. pulled most of its staff from Cuba after accusing the communist government of allowing what the U.S. calls “health attacks” that have sickened more than two dozen embassy staff who were stationed in Havana. Cuba denies any involvement in aggression against diplomats and says the U.S. has failed to provide any evidence backing up its claims of deliberate actions against diplomats.

Canada on Thursday said it was considering all options regarding its embassy in Cuba after another of its diplomats was found to have fallen mysteriously ill, bringing the total to 13.

Tablada said Canada had reacted in a measured and professional way to reports of health problems but the U.S. was using the incidents and tensions over visas to conduct a stealth rollback of detente.

“We find ourselves today facing a situation in which, faced with the impossibility of finding popular support for imposing a rollback, they’re cold-bloodedly inventing reasons, and inventing them in a deceptive way,” she said.

Tablada said the U.S. had waited until Thursday to grant a visa to a deputy minister of foreign trade investment who had been invited to preside at a U.N. meeting in New York, which she missed. The delay violated the United States’ obligations as the U.N. host country, Cuban officials said.

The U.S. State Department said blame fell on Cuba.

“The Cuban government has failed to issue visas to U.S. diplomats in a timely and consistent manner,” the State Department said in a brief statement. “Both governments maintain the sovereign right to issue or deny visas to specific individuals.”

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