The president of the European Council has told the UK that the only real alternative to a “hard Brexit” or clean break from the EU is to remain a full member of the bloc.

Speaking at a conference in Brussels, Donald Tusk dashed the hopes of those hoping Britain could remain inside the EU’s single market or negotiate some special form of association. The tenor of the UK’s referendum campaign had been to “radically loosen relations with the EU, something that goes by the name of ‘hard Brexit’,” he said.

“In my opinion, the only real alternative to a hard Brexit is no Brexit,” Mr Tusk said. “Even if today hardly anyone believes in such a possibility.”

Since Theresa May, UK prime minister, suggested London would opt for a clean break from membership of the single market in her party conference speech this month, the pound has taken a battering on foreign exchange markets as investors worry about the economic implications.

In remarks that are likely to infuriate prominent Brexiters in the British government, Mr Tusk set out a bleak picture for the negotiations to come between the UK and the rest of the EU, saying that there would be no winners, only losers. “This scenario will in the first instance be painful for Britons,” he said.

Paraphrasing UK foreign secretary Boris Johnson’s campaign trail claim that a post-Brexit Britain would “have the EU cake and eat it too”, Mr Tusk said: “The brutal truth is that Brexit will be a loss for all of us. There will be no cakes on the table for anyone. There will only be salt and vinegar … The words uttered by one of the leading campaigners for Brexit …[were] pure illusion.”

Taking questions after the speech, Mr Tusk extended an olive branch to London, saying that he had not encountered a single leader on the continent “who is happy with this result of the British referendum”.