Britain's armed forces face a £10bn ($12.5bn) funding shortfall, it has been reported. According to The Times, military heads have started reviewing their budgets in an effort to find an additional £1bn per year in savings, on top of previous cuts, for the next decade.

Some chiefs have also reportedly approached Defence Minister Michael Fallon about the crisis, but have complained that the government is currently too distracted by Brexit.

The Times spoke to seven current and former military officers to establish the extent of the problem.

"All of the services are looking at a picture where they cannot afford their current programmes," one senior officer said.

Costly Trident renewal

One area adding to the funding pressure is the decision to renew the Trident nuclear deterrent's submarine programme, which is believed to cost $47bn compared to the initially estimated £41bn.

An additional £6bn is said to be required for support items for ships, tanks and jets. Brexit will also exacerbate the problem, increasing the armed services' exposure to foreign exchange rates by £3bn as the value of the pound is expected to decrease.

As a result of the shortfall, the capability of the Royal Marines will reportedly be cut – removing one of its three frontline commando units and suspending its overseas training.

A Ministry of Defence (MoD) spokesman said it was not clear how The Times reached its £10bn shortfall figure and therefore he could not comment on its accuracy.

The spokesman added: "Spending is monitored continually to ensure the £35bn defence budget focuses on frontline priorities and delivers value for money by maximising efficiencies."