LEAVE.EU has been the subject of a furious backlash after posting a distasteful tweet about the German chancellor.

Earlier today, a Downing Street source said that agreeing a deal with the EU was “essentially impossible” following a telephone conversation between Angela Merkel and Boris Johnson.

According to the Number 10 source, Merkel made clear that a deal based on Johnson’s latest proposals is “overwhelmingly unlikely".

READ MORE: Poll: voters will blame Parliament more than Johnson if Brexit delayed

The claim led Leave.EU to take to Twitter to hit out at the German chancellor.

Their tweet included a graphic of Merkel with the words: “We didn’t win two world wars to be pushed around by a kraut.”

The anti-EU campaign group – co-founded by Aaron Banks – wrote on the tweet: “Angela Merkel's demand that Britain leaves Northern Ireland to rot inside the customs union is reprehensible and shows the true colours of our supposed ‘European allies’.

“Enough of this nonsense, we walk away as an independent, self-governing nation in three weeks' time!”

Among the thousands of replies, University of Surrey politics and philosophy lecturer Adrian Hutton wrote: “Appalling tweet. Please delete it.”

The Times’ diplomatic correspondent Cathrine Philip added: “Utterly disgraceful.”

Another Twitter user, Anja Nijenhuis, said: “You are giving the UK really a bad reputation. Greetings from the Netherlands.”

Comedy writer James Felton pointed out: “You didn’t win two world wars though, did you? Stop acting like you personally stormed the beaches of Normandy as a sperm you massive f***ing racists.”

Another Twitter user posted: "Disgraceful stuff. We aren't at war with Germany anymore! Jingoistic language like this may inflame those so inclined, but not the majority of our population!"