The US has expelled 15 Cuban diplomats, saying Havana failed to protect US diplomats from mysterious acoustic attacks, the BBC reported on Tuesday.

The Cuban personnel have been given seven days to leave.

The US Department of State's move follows last week's US withdrawal of more than half of its own diplomats from the Cuban capital.

"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," US Secretary of State Rex Tillerson said in a statement on Tuesday.

At least 21 people working at the US's embassy in Cuba have reported health problems, ranging from mild brain trauma and deafness to dizziness and nausea.

Earlier reports suggested sonic attacks were to blame, but nothing has been proven.

Cuba denies targeting embassy staff, and the US has not blamed the country's government for the suspected attacks.

Source: MENA