The former London mayor said the goal of officials in Brussels was to create a European super-state
The Former London Mayor Boris Johnson has been condemned for comparing the expansion of the European Union to Hitler's attempts to conquer Europe.
In an interview with the Sunday Telegraph, the Brexit campaigner said previous leaders such as Hitler and Napoleon attempted a similar goal, albeit using different methods.
"Various people tried this out, and it ends tragically", he said.
"Fundamentally what is lacking is the eternal problem, which is that there is no underlying loyalty to the idea of Europe".
Johnson has made a series of gaffes during his campaign to leave the EU, first claiming Barack Obama's "part-Kenyan" heritage made him hostile to the "British empire" and then claiming EU foreign policy stoked tensions in Ukraine.
He was called a "Putin apologist".
UK Labour leader Jeremy Corbyn told ITV: "Boris Johnson has some very odd interpretations of history."
While, former UK Labour MP Yvette Cooper accused him of playing a "nasty, nasty game".
"The more he flails around with this kind of hysterical claim, the more he exposes his shameful lack of judgement, his willingness to play the most divisive cynical politics, and the emptiness of his arguments," she said.
But Tory MP Jacob Rees-Mogg said Johnson's remarks were "absolutely true".
He said "Philip II of Spain, Louis XIV of France, Napoleon and Hitler all wanted to create a single European power.
"What Boris has said is the EU is following the footsteps of these historic figures but using different means."