EU referendum: Boris Johnson's Hitler comparison drags Donald Tusk into Brexit debate

EU grandee Donald Tusk has intervened in the UK's referendum campaign after Boris Johnson compared the political and economic union to Nazi Germany. The Polish European Council president said he could not remain silent after the Brexit campaigner made the controversial comments.

"Such absurd arguments should be completely ignored if they hadn't been formulated by one of the most influential politicians of the ruling party," Tusk declared. "Boris Johnson crossed the boundaries of a rational discourse, demonstrating political amnesia.

"In some sense, he illustrated a state of minds and emotions of many Europeans, not only from the UK. In no way, however, can this be an excuse for this dangerous blackout.

"The EU may be blamed for many things, but it still remains the most effective firewall against the ever-dangerous, and often tragic conflicts among the nations of Europe."

Tusk also took on the claim that the 28-nation-bloc was a superstate. "European countries would have to face the migration crisis, an aggressive Russia and economic uncertainty also without the EU," he said. "The question is whether individual countries can better cope with the problems on their own. At least to me, the answer is clear."

The intervention came after Johnson told The Telegraph: "Napoleon, Hitler, various people tried this out, and it ends tragically. The EU is an attempt to do this by different methods." The Vote Leave spokesman has since defended his remarks, blaming media "hysteria".

"This discussion is bedevilled by all sorts of artificial media twit-storms or hysteria of one kind or another. There's a very good argument against the lack of democracy in the EU," Johnson told the BBC News channel. "Over the last 2,000 years people have made repeated attempts to unify Europe by force. The EU is a very different project but it is profoundly antidemocratic."