The Trump administration on Tuesday ordered Cuba to withdraw 15 of its diplomats from the US within seven days, responding to what Washington said was Havana's failure to protect US diplomats in Cuba.

Speaking on the condition of anonymity, a US state department official told reporters during a conference call that the department had communicated the demand to Cuban Ambassador Joe Ramon Cabanas.

Shortly thereafter, US Secretary of State Rex Tillerson said in a statement that the decision was a response to "Cuba's failure to take appropriate steps to protect our diplomats." He added that the move would "ensure equity" in staffing levels between the countries' respective embassies.

Multiple unexplained attacks in recent months left twenty-two US diplomats at the embassy in Havana with health issues including hearing loss, fatigue, and cognitive issues.

Washington responded to those attacks last Friday by announcing it would withdraw nearly two-thirds of its embassy staff from Havana. It has also warned its citizens not to travel to the island nation.

Those moves had followed the US's decision in August to expel two Cuban diplomats.

Cuba has repeatedly denied any involvement and criticized the US decision to withdraw its staff as "hasty."

Speaking on Tuesday, the state department official said the administration was not trying to signal that it blamed Havana for the mysterious attacks. He added that the 15 diplomats would not be permanently barred from returning to the US.

Tillerson also said the US would "continue to maintain diplomatic relations with Cuba and will continue to cooperate with Cuba as we pursue the investigation into these attacks."

The ongoing diplomatic saga marks a further setback for US-Cuba ties at a time when the historically troubled relationship has been worsening.

Former US President Barack Obama reestablished diplomatic relations with Cuba in 2014 after more than a half-century of hostility. But US President Donald Trump has since rolled back some of Obama's measures that were designed to improve bilateral ties.

amp/msh (Reuters, AP)