Britain was forced to ground all 16 of its new F-35 fighter jets after the US government discovered that a faulty fuel tube was behind a crash last month. 

Checks were being carried out to see whether the F-35s, the most advanced fighter jet ever created, have the same tubes as those which were used in the plane which went down. 

The US government announced on Thursday that flights of the jet would be paused as a precaution, prompting Britain and other military allies such as Israel to follow suit. 

It is an embarrassing development for the F-35 programme, the largest and most expensive weapons project of its type in the world. 

The planes are designed to be the next generation of fighter jets, capable of carrying bombs and missiles but also rigged up with cyber capabilities – seen as a critical function for 21st century battlefields. 

The programme is being run out of America and a total of 3,000 jets are set to be created ultimately, with many being sold overseas. 

Britain has committed to buying 138 F-35s and paid for 48, with just 16 completed so far. Nine of these are currently in the UK and seven still in America. 

The new complication emerged after an F-35B Lightning II stealth crashed near Beaufort, South Carolina last month.  The US pilot was safely ejected and there were no civilian casualties. 

The cause of the crash was a mystery at the time, but it has since emerged that a faulty fuel tube in the engine played a role.

America, British and other military officials were carrying out checks on all F-35s on Thursday – both looking at paperwork and inspecting engines – to see whether the jets used the same type of fuel tube. 

A Pentagon official said: “If suspect fuel tubes are installed, the part will be removed and replaced. If known good fuel tubes are already installed, then those aircraft will be returned to flight status. Inspections are expected to be completed within the next 24 to 48 hours.”

The official added: “The primary goal following any mishap is the prevention of future incidents. We will take every measure to ensure safe operations while we deliver, sustain and modernise the F-35 for the warfighter and our defence partners.”

A Ministry of Defence spokesman said: “Safety is our paramount concern, therefore the UK has decided to pause some F-35 flying as a precautionary measure while we consider the findings of an ongoing enquiry.”

At least one British-owned F-35 was cleared and was back in the air on Thursday.  The problem has emerged just weeks after F-35 jets landed on HMS Queen Elizabeth, Britain’s new aircraft carrier, for the first time. 

Journalists were invited on-board for the ceremony, which was seen as a show of the UK’s military might. The type of F-35 Britain has purchased is able to hover before touching down. 

Gavin Williamson, the Defence Secretary, said at the time: “The largest warship in British history is joining forces with the most advanced fighter jets on the planet. This marks a rebirth of our power to strike decisively from the seas anywhere in the world.”

He added: “It is also a statement of Britain’s determination to promote peace and prevent war.”