The President of the European Commission said the European Union’s hands were “outstretched” to welcome Britain back into the bloc.
Speaking in European Parliament, he said: “When it comes to Brexit I am sure that there will be no winners from this situation.
“This is a lose-lose situation, it’s a lose-lose situation both for the British and for the members of the European Union.
“I continue to feel that the exit of Great Britain is a catastrophe.
“It is a defeat that we all have to deal with the consequences of but the causes of the British decision run much deeper.
“As Mrs May has said the British have never felt entirely comfortable with the European Union so the guilt lies upon many shoulders.
“Mr Tusk said that our hands remain outstretched.
“The British people, the British government may wish to find a different way out of the Brexit situation, we’re very much willing to deal with them.
“We are not throwing the British out, we would like the British to stay and if they so wish they should be allowed to do so.”
Mr Juncker also addressed outrage by Brexiteer’s over the EU’s attempts to bring Britain back into the fold on Tuesday.
He said: “I did note that in London, there was a rather irritated response to this proposal.
“Note that even if the British leave, according to Article 50, then Article 94 would allow them to exit again.
“I would be happy to facilitate that so I certainly wouldn’t want to push anyone into a corner.”