The United States has expelled two members of the Cuban mission to the U.N., accusing them of trying to “conduct influence operations” against the U.S.

The State Department did not identity the two Cubans or give any information on what they are accused of doing.

Spokeswoman Morgan Ortagus said they “abused their privileges of residence.” She said the remaining members of the Cuban mission will be restricted to New York’s Manhattan island, where the mission and U.N. headquarters are located.

Cuban Foreign Minister Bruno Rodriguez called the expulsions “unjustified,” adding on Twitter that “the imputation that they might have carried out actions incompatible with their diplomatic status is a vulgar slander.”

Relations between the U.S. and Cuba improved tremendously under former U.S. President Barack Obama. Diplomatic ties were restored in 2015 for the first time in more than 50 years.

But relations have cooled off during the Trump presidency. Both countries exchanged tit-for-tat expulsions in 2017 after U.S. diplomats and others in the embassy in Havana came down with mysterious illnesses. The State Department believes the sickness was caused by high-pitched sounds targeting the embassy. The U.S. blames Cuba, which denied responsibility.

Trump is also angered over Cuban support for the Maduro regime in Venezuela.