Hammond 'banned' until he settles bill for chopper flights to the Black Country

The Chancellor's department is said to owe a six-figure sum for flights with No 32 (The Royal) Squadron. Reports suggest he has been banned from using the fleet until he settles the bill.

It comes as new Defence Secretary Gavin Williamson prepares to fight the Treasury for an extra £2 billion a year funding for the armed forces in a bid to prevent cuts to service personnel.

It is understood that the Chancellor used BAe146 jets – which are also used to transport the Royal family – and A109 helicopters to fly to more than 20 destinations this year on official business.

They included a visit to Dudley College in March, where he announced funding plans for the Midlands Engine.

He is also said to have used MoD transport on a trip to the Express & Star's Queen Street offices two days before the General Election in June.

The Prime Minister, Foreign Secretary Boris Johnson and Brexit Secretary David Davis also have permission to use the fleet, which operates from RAF Northolt in London.

They are all understood to have covered their costs.

Mr Hammond, who was Defence Secretary from 2011 to 2014, has been accused of telling Theresa May to cut the strength of the Army from 77,000 to as few as 50,000.

Mrs May could be set to meet Mr Williamson and Mr Hammond as early as next week to discuss funding for the armed forces.

A national security capability review that is being overseen by the Cabinet Office is currently underway.

Mr Williamson, who replaced Michael Fallon as Defence Secretary on November 2, has said he sees Britain's current military spend of two per cent of GDP as 'a bare minimum'.

He is expected to fight against cost saving options such as reducing Royal Marine numbers by up to 1,000, and delaying an upgrade to Army tanks and armoured vehicles.