CUBA hit back at increasingly far-fetched US claims of attacks on its diplomatic staff on Tuesday.

Cuban Foreign Ministry US division director Josefina Vidal called renewed allegations at a meeting of the US Senate foreign relations committee “political manipulation.”

“The biggest victim of today’s hearing was the truth,” she said.

At the Washington hearing, State Department diplomatic security service assistant director Todd Brown made new claims of a “virus” attack to explain health complaints by 24 staff and their spouses at the US embassy in Havana — without providing evidence.

That came just days after the FBI found no evidence of “sonic attacks” with high-pitched noises.

He claimed even if the strange sounds heard by the vast majority of the 24 “medically confirmed” US patients did not cause their complaints, “the acoustic element could be used as a masking piece.”

“We are not much further ahead than we were in finding out why this occurred,” Undersecretary of State Steve Goldstein admitted after the hearing.

But he insisted Cuban President Raul Castro’s government “knows what occurred” and refuses to tell the US.

The incident was used as a pretext for the State Department to withdraw 60 per cent of its staff from the embassy and expel 17 Cuban diplomats from Washington.

The re-establishment of the embassies in 2015 was a major breakthrough in bilateral relations.

Ms Vidal singled out Republican Florida Senator Marco Rubio, a longstanding supporter of the six-decade US blockade on Cuba who co-chaired the session with New Jersey Democrat Robert Menendez.

“They have been promoters of legislations that affect the interests of both nations and only benefit a minority which continue to be isolated and have made a living with US aggression,” the Cuban News Agency quoted her as saying.

She reiterated that Cuba is a safe, peaceful and healthy country for Cubans, foreigners and diplomats accredited there and for the millions of people that visit the country each year, including many from the US.

On Saturday, Republican committee member and Arizona Senator Jeff Flake — a leading advocate of detente with Cuba — said he had received an intelligence briefing.

Mr Flake spoke during a trip to Havana, where on Friday Cuban Foreign Minister Bruno Rodriguez told him four FBI investigative delegations had failed to find any evidence of the claimed “sonic attacks.”