Forty million pounds of cocaine will never reach the streets after a combined Anglo-French-American bust in the Caribbean which snared a drug-running team.

Support ship RFA Mounts Bay, a Falmouth based ship and a US Coastguard team pounced on two speedboats as they raced through open seas south of the US Virgin Islands.

They seized 1.4 tonnes of illegal narcotics – which turned out to be cocaine, worth more than £35m.

The traffickers managed to ditch 150kg of drugs in the Caribbean before they were intercepted – ensuring another £3.75m of cocaine won't be sold.

"Thanks to the work of the Royal Navy and our US partners these narcotics will not reach the streets and fuel further criminality," said Armed Forces Minister Anne-Marie Trevelyan.

"RFA Mounts Bay has had a varied deployment, from leading the response to Hurricane Dorian to stopping the illicit drugs trade. This is a timely reminder of the diverse work undertaken by our Armed Forces that helps keep us safe."

It's the second bust in a week scored by UK Naval forces; just a few days ago HMS Defender captured £1m of cannabis from a dhow on the Hash Highway in the Middle East. Mounts Bay has been on counter-drugs patrol since the beginning of the year, taking part in a combined UK-US-French operation, Carib Royale.

Aboard the Falmouth affiliated ship is a specialist board-and-search team of US Coastguard personnel – the Law Enforcement Detachment – and their MH65 helicopter.

That helicopter was on a patrol when it came across a 'go-fast' craft – typical of those used by smugglers in the region.

Mounts Bay changed course to intercept and once within close range, sent the Coastguard detachment across to stop the craft and seize its cargo.

The boarding team found 44 large bales of cocaine – and learned from the five-strong crew that they had succeeded in jettisoning 150kg, about one-tenth of their cargo, before they were halted in the tracks.

Also intercepted was a second go-fast carrying oil drums and pumps to transfer fuel to the first boat, as well as two crew.

All seven prisoners and the drugs haul were transferred to Mounts Bay – where the latter were weighed, tested and recorded as evidence.

"The 'Bay team' has dealt another big blow against drug traffickers – £40m of drugs will never plague the streets and ruin lives thanks to our efforts. Everyone aboard Mounts Bay has a right to feel proud of the part they played in the bust," said Captain Kevin Rimell RFA, Mounts Bay's Commanding Officer.

"This successful interdiction comes at the end of Mounts Bay's three-year deployment epitomises the capability of the ship and the assets we have embarked, along with the unique co-operation that exists between the UK and US and our military organisations."

The detainees and drugs were later handed over to the US Coast Guard for authorities in the USA to consider prosecution.

Mounts Bay is coming to the end of her patrol of the Caribbean, spending the winters and springs supporting the international fight against drug trafficking, and the summers/autumns providing assistance in the wake of the frequent storms barrelling through the region, such as helping islanders in the Bahamas after Hurricane Dorian last year.

She's being replaced by new patrol ship HMS Medway which will be permanently stationed in the Caribbean.