DAVID Cameron has been accused of "doing a runner" after his policy of "placating fruit cakes and loonies" led to the UK voting for Brexit.

Dave Anderson, the MP for Blaydon and newly-appointed shadow Scottish secretary and shadow Northern Ireland secretary, used his frontbench debut to hit out at the Prime Minister's decision to step down in the wake of the EU referendum.

Mr Anderson was appointed to the two roles after Ian Murray resigned as shadow Scottish secretary and Vernon Coaker resigned as shadow Northern Ireland secretary in protest over Jeremy Corbyn's leadership of the Labour Party.

And the long-serving backbencher wasted no time in attacking Mr Cameron over the PM's decision to walk away from Number 10 as he went toe-to-toe with Scottish Secretary David Mundell for the first time.

Speaking during Scottish questions, Mr Anderson said: "The chair of the Foreign Affairs Committee was absolutely right yesterday to accuse our hapless Prime Minister of being guilty of a dereliction of duty for failing to set up withdrawal planning units for after the referendum.

"Would someone please tell the Prime Minister the words to the song aren't 'when the going gets tough, the tough do a runner'?

"With that in mind, can I ask the Secretary of State if he believes that the Prime Minister's policy of placating fruit cakes and loonies has been a price worth paying for the economic crisis that is now upon us, and the risk of a break up of the United Kingdom?"

However, Mr Mundell insisted the will of the British people must be respected after a majority voted for the UK to leave the EU.

"I'm a democrat," he said.

"I respect the democratic decision of the people of the United Kingdom and that decision will be implemented."

Mr Mundell said the Scottish government will be "at the heart" of the UK's exit negotiations with the EU.

He also confirmed that he and Oliver Letwin, the man in charge of the Brexit unit within the Government, will meet with Nicola Sturgeon next week to discuss the negotiations.