STRASBOURG/BRUSSELS - The European Union delivered a stark warning on Wednesday that Britain was headed for a damaging no-deal Brexit, with London’s ideas on replacing the contentious backstop to unlock an accord falling short just six weeks before Britain is due to leave.

Addressing EU lawmakers sitting in Strasbourg, European Commission President Jean-Claude Juncker said British Prime Minister Boris Johnson had told him on Monday that London still wanted a deal, but would leave with or without one on Oct. 31.

Pro-Brexit lawmakers cheered and applauded in the chamber.

“There is very little time left...The risk of a no-deal is very real,” said Juncker, his comments weighing on the sterling.

EU leaders will meet for a make-or-break summit in Brussels on Oct.17-18, just a fortnight before Brexit is due to materialise more than three years after Britons voted to leave.

But U.S. investment bank JPMorgan sounded negative on Wednesday about the prospects of Johnson striking a deal then after recent rounds of talks between the two sides showed significant gaps remain.

Britain is not likely to present a complete set of detailed, written proposals of how it would want the text of the existing - but stalled - Brexit deal changed before the end of the month, UK and EU sources said.

“If that is the case, the summit will end with nothing,” an EU diplomat dealing with Brexit in Brussels said. “If there is to be a deal, it must be prepared to a large extent in advance. It is too technical to leave to the leaders at the last minute.”

“A clear outline must be there in advance. Expecting that the leaders would suddenly come up with a magical solution to such complex matters is completely unrealistic.”

In a worst case scenario, a no-deal Brexit could mean severe disruption to trade, supplies of medicines, fresh foods and a possible rise in public disorder, according to the British government’s contingency plans.

Such a sharp break in economic ties, ending four decades of EU membership, “might be the United Kingdom’s choice, but never the choice of the EU,” Juncker said, highlighting how the bloc wants to avoid blame if Britain crashes out.

Juncker said London must present realistic proposals to replace the Irish backstop arrangement in the Britain-EU divorce agreement, which former premier Theresa May agreed with EU leaders but which was rejected by the British parliament.

“I am not emotionally attached to the Irish backstop,” Juncker said. “I have asked the prime minister to make, in writing, alternatives,” he said, calling it a safety net to avoid a divided Ireland after Brexit.

His pessimistic tone was echoed by Finland’s minister for European affairs, Tytti Tuppurainen, who also spoke in the parliament, saying a no-deal Brexit “is a quite likely outcome.” Finland holds the EU’s rotating presidency.(FA)