Theresa May has faced fresh warnings from her front bench to increase military spending, with a minister claiming a strong economy “cannot be guaranteed” without strong defence.

Tobias Ellwood thanked the Treasury for providing an “extra £200 million window” to allow the Ministry of Defence (MoD) to “close the books” on the 2017/18 financial year, telling MPs this was new cash.

But the defence minister cited concerns over a potential training backlog and the “financial pressure” the equipment programme is under.

He insisted the Nato target of spending 2% of GDP on defence is “just not enough” if the UK wants to continue playing an influential role post-Brexit.

Defence minister Tobias Ellwood speaks during a Commons debate on defence spending
Defence minister Tobias Ellwood speaks during a Commons debate on defence spending (PA)

Mr Ellwood recognised the MoD can make efficiencies, but said that as the “world gets more complex and more unpredictable” the UK’s economy and values are “vulnerable to a range of growing dangers that have no respect for our borders”.

He said it was in the UK’s DNA to help shape the world, adding to the Commons: “To continue to do so will require investment.

“So I end by repeating my thanks to the Treasury for their support. I know they have to endure all Whitehall departments seeking to increase their budgets.

“We often say with only a strong economy can we consider any increases to any budgets. But I politely add that without a strong defence, a strong economy cannot be guaranteed.

“Last week the Defence Secretary (Gavin Williamson) spoke about the 2% defence spending being a floor not a ceiling.

“Well, the message has to be clear – if we want to continue playing an influential role on the international stage with the full spectrum capability, if we want to provide the critical security post-Brexit trade deals will demand, if we want to remain a leading contributor in the fight against extremism in the Middle East and elsewhere, you cannot continue to do this on a defence budget of just 2% – 2% is just not enough.

“This is a question not just for this Government, not just for parliamentarians, but for Britain. What status, what role, what responsibility do we aspire to play as we seek to trade more widely in a world that is becoming more dangerous?”

Mr Ellwood’s comments came after former defence minister Mark Francois said the “pinstriped warriors of the Treasury” should be taken to see the film Darkest Hour in the hope it may bolster Britain’s determination to defend itself.

Conservative MP Mr Francois said the film depicting Sir Winston Churchill showed what happened when the armed forces were run down “to the point where they were unable to deter war”.

A number of other Tories also renewed calls for the Government to boost spending beyond the existing target of 2% of GDP.

Shadow defence secretary Nia Griffith said there was “deep dissatisfaction” at the state of the defence budget on all sides of the House and a “real desire” for “proper investment”.

She said: “Defence spending has been cut by nearly £10 billion in real terms between 2010 and 2017.”