Boris Johnson, then mayor of London, and George Osborne, then chancellor, visit the Battle of Britain Bunker in Uxbridge. (PA)

George Osborne has accused Boris Johnson of using Brexit for his own political gain and abandoning his “liberal” principles “to get to the top”.

The former chancellor spoke to former leader of the Scottish Conservatives Ruth Davidson in a candid interview for radio station LBC on Monday.

During the interview he was asked by Ms Davidson about how he would compare the Boris Johnson he knew before he became prime minister to now.

“One of the good things about my life is I’ve known Boris Johnson for 25 years and he is enormously entertaining and engaging – and also a contradiction,” he said.

View photos Boris Johnson addresses British soldiers after serving Christmas lunch to troops stationed in Estonia on Saturday. (AP) More

“He is a very talented, brilliant political operator, but often he’ll adopt causes to get himself to the top that I don’t agree with - including Brexit.”

Mr Osborne compared the prime minister to a Jekyll and Hyde character who is able to switch between conflicting political views.

“I always think when I look at Boris, I think he’s got what it takes to be the prime minister and he clearly fills the job,” he said.

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“But I kind of wish he was the Dr Jekyll side of Boris Johnson, which is the sort of liberal, tolerant, pro-immigration, centrist Tory who was so successful in the city of London.

“And not the Mr Hyde who wants to sort of divide the country, push Brexit to its political limits in order to eek out the advantage amongst the Brexiteers.”

Mr Osborne, who campaigned for Remain prior to the 2016 referendum, appealed to Mr Johnson to rediscover the views he championed during his stint as mayor of London.

“I think he would be much better served being the Boris Johnson who was a very successful mayor,” Mr Osborne continued.

“There are glimpses of it. I still think he’s got it in him to be a very successful prime minister. But I think he should be the prime minister for the 17 million people who voted Leave, and also the 16 million who voted for Remain.

“I think his basic political instincts, beneath all the layers of calculation, are the right ones.”

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