Britain’s former prime minister David Cameron has resigned from his seat in parliament, ending his political career just weeks after he lost a referendum to stay in the European Union.

He said he wanted to avoid becoming a distraction for his successor.

Cameron, who came to power in 2010, said he had told Prime Minister Theresa May of his decision to stop representing his constituency in Oxfordshire to make way for someone who could concentrate on the area in central England.

David Cameron leaving Downing St on July 13 with his family after losing the Brexit vote. Photo: Karwai Tang/Getty

“I’ve thought about this long and hard over the summer and I’ve decided the right thing to do is to stand down as the member of parliament for Witney,” he told BBC TV.

“In my view with modern politics, with the circumstances of my resignation, it isn’t really possible to be a proper back bench MP as a former prime minister.

I think everything you do will become a big distraction and a big diversion from what the government needs to do for our country.”

His resignation is effective immediately and there will be a by–election in Witney, a seat he has held since 2001.

Cameron, 49, stepped down as prime minister in June shortly after 52 per cent of Britons ignored his pleas and voted to leave the European Union. He said the country needed “fresh leadership” to negotiate the country’s exit, or Brexit.

Cameron had sat on the ‘back benches’ of parliament several times since he quit the top job, but made little impact.

He had earlier said he would complete his term in office until the next election due in 2020.

May has moved to distance herself from some of Cameron’s policies, particularly in education where she has ditched his pledge not to increase the number of selective state schools.

Former Cabinet minister Ken Clarke said he was “disappointed” by Mr Cameron’s decision but said the “chickens came home to roost” after the referendum.

He told BBC News: “I’m a friend of David’s, so I regret to say, I think for history his legacy will be he’s the man who accidentally caused Britain to leave the European Union.

“There’s no getting away from the fact that that will overshadow every other feature of his premiership.”

"Brits don't quit" – David Cameron (June 2016)… except when we don't get our own way, we quit twice in 4 months #Cameron

— Will Hingley (@Will_Hingley) September 12, 2016

Labour leadership contender Owen Smith said: “David Cameron’s legacy will be a country left reeling after six years of failed Tory austerity.”

Former No 10 communications director Sir Craig Oliver said Mr Cameron did not want to be seen as a “back seat driver”.

“He doesn’t want to be the person that people go to cause disagreement or have disagreements with the Government.”