The United States has ordered the expulsion of 15 Cuban diplomats from the country after removing 60 per cent of its staff from its embassy in Havana.
US Secretary of State Rex Tillerson said that the Cuban government had failed to protect US diplomats and their families from unexplained sonic attacks.
"The decision was made due to Cuba's failure to take appropriate steps to protect our diplomats in accordance with its obligations under the Vienna Convention. This order will ensure equity in our respective diplomatic operations," Mr Tillerson said in a statement on Tuesday.
He added: “Until the Government of Cuba can ensure the safety of our diplomats in Cuba, our embassy will be reduced to emergency personnel to minimize the number of diplomats at risk of exposure to harm.”
“We continue to maintain diplomatic relations with Cuba, and will continue to cooperate with Cuba as we pursue the investigation into these attacks.”
Cuba’s foreign minister Bruno Rodriguez said the decision was “unjustified”, while accusing the US of not cooperating sufficiently with the investigation into the causes of the incidents.
US state department officials said the expulsions were not meant as punishment but instead were intended to ensure the US and Cuban embassies had equitable staffing levels.
Since last week the number of diplomats confirmed to be suffering from symptoms, including dizziness, hearing loss and nausea, has increased to 22.
The US issued a new travel warning on Friday, while pulling more than half of its staff from the embassy, which reopened in 2015 under the Barack Obama administration following the resumption of diplomatic ties between the two nations.
However, current US president Donald Trump, who has announced a partial roll-back of his predecessor’s policies, said he would shut the embassy again if necessary.