The Government insists Operation Yellowhammer is a "worst case scenario", despite claims from Labour the no-deal Brexit plans are more like "emergency planning for a war or natural disaster".

Defence Secretary Ben Wallace said documents relating to the Government's no-deal Brexit contingency planning, named Operation Yellowhammer, represent a "worst case scenario" plan, and that the Government is working "every day" to mitigate the potential effects.

The papers, released by the Government, set out how the UK might be affected by a no-deal Brexit, with some possible disruption including delays in importing medicines, and disruption at ports and borders.

Speaking on BBC Radio 4's Today programme, Wallace said Yellowhammer is a "planning assumption", but stressed that it is only what might happen if the Government was to do nothing to mitigate it.

He said: "That is why we are doing things about it. That is why the Chancellor opened his cheque book, that's why we are spending the money on doing lots of things to mitigate those assumptions."

Wallace said: "Every day, we plan everything from whether we need to find alternative suppliers, whether we need to go out to the private sector to charter things, whether we need to plan using our army or our police forces in certain scenarios."

Labour, however, said the papers prove it would be a "catastrophe" if the UK leaves the EU without a deal.

Shadow transport secretary Andy McDonald said Parliament should be recalled immediately so the Prime Minister can answer questions in relation to Operation Yellowhammer, which he said is more like planning for "war or a natural disaster".

The National: Shadow transport secretary Andy McDonald (centre) said Parliament should be recalled immediately.Shadow transport secretary Andy McDonald (centre) said Parliament should be recalled immediately.

Speaking on the Today programme, McDonald said: "It reveals an absolute catastrophe for our country if he continues to drive the ship towards the rocks as he is going to do."

He added: "This is more like emergency planning for war or a natural disaster. We can not minimise this. It does not get more stark, and we have got to wake up to the issues around us."

McDonald said Labour wants to stop a no-deal Brexit and gain an extension to Article 50. He said when an extension is obtained, Labour would favour a general election.

He said the public would be offered a referendum with a "credible deal" opposite a remain option.

Former Tory attorney general Dominic Grieve said the level of disruption set out in the Yellowhammer papers is "unprecedented".

He said it is good that the Government is making plans, but warned that the disruption "inflicted" on the British public would be damaging.

Speaking on the Today programme, Grieve said: "I am pleased they are taking contingency plans, but it is still the most extraordinary document.

"This is a government which, in peace time, is content on inflicting on the British public the level of disruption which is set out in the Yellowhammer papers.

"It is unprecedented. I can't think of an occasion where I have seen something of this kind before."

Grieve added: "Even if we are ready for a no-deal Brexit, this is highly disruptive and costly. And I think the issue here is that the public should have a proper understanding of the sort of level of disruption that no deal is going to cause."

Grieve accused the Government of "trashing the constitution", but said he still hoped to find a way forward that would be "acceptable to everyone".

He said: "The Government is conducting itself in a thoroughly un-Conservative way, trashing the constitution and letting out, saying the most extraordinary things, including allowing Number 10 to launch attacks on the judiciary until they were stopped by the Lord Chancellor.

"This, I have to say, is not a party I recognise. I would love to cooperate with my Conservative colleagues and, indeed, with the Prime Minister to try to find a sensible way out of the Brexit crisis that can be acceptable to everyone, including those who voted Leave and are still promoting Leave."