LUXEMBOURG — Britain has not proposed any workable alternatives to its Brexit withdrawal agreement, the EU said Monday after talks with UK Prime Minister Boris Johnson ended without a breakthrough.

It said the meeting between Johnson and EU Commission president Jean-Claude Juncker failed to yield any alternative to proposals on the Northern Ireland border that the British leader has rejected.

Johnson has vowed to take Britain out of the bloc by the scheduled date of Oct. 31, though parliament has ordered him not to do so without striking a deal with Brussels first.

Businesses and opponents of Brexit say leaving without a deal will cause economic chaos as Britain ends its open trade ties to the European Union after 46 years.

After a weekend in which he compared himself to comic book super-smasher Hulk, the British leader enjoyed a genteel working lunch of chicken and pollock with Juncker in Luxembourg.

Downing Street billed the Luxembourg visit as part of efforts to negotiate an orderly divorce from the union before an Oct. 17 EU summit.

It insisted it had been a "constructive meeting" and said the two sides had agreed to step up the pace of talks with daily meetings between negotiators.

But the commission gave a more sober assessment, saying that once again the UK had failed to come up with a viable alternative to the so-called Irish "backstop" border arrangement.

"President Juncker recalled that it is the UK's responsibility to come forward with legally operational solutions that are compatible with the Withdrawal Agreement," a statement from Juncker's office said.

"President Juncker underlined the Commission's continued willingness and openness to examine whether such proposals meet the objectives of the backstop. Such proposals have not yet been made."

Johnson says Britain will not agree to a divorce deal that includes the backstop, a provision that would temporarily keep the UK in the EU customs union to keep the Irish border open.

He says he will not delay Brexit beyond Oct. 31 even if it means leaving with no deal.

A small but noisy clutch of anti-Brexit protesters greeted Johnson as he arrived and left the talks, singing the "Ode to Joy" EU anthem, waving flags and chanting slogans.

Before the talks, a UK spokesman stressed London's view that progress was being made in talks between officials to try to find a backstop alternative, but this note of optimism finds no echo in European capitals.

Finland's European affairs minister, Tytti Tuppurainen, who was chairing an EU ministerial meeting in Brussels, said London had not come up with detailed ideas for replacing the "backstop" section of the divorce deal.

"The European Union is always ready to negotiate when a proper proposal from the UK side is presented," Tuppurainen said.

"So far I haven't seen any proposal that would compensate the backstop."

The EU's chief Brexit negotiator Michel Barnier, who joined the leaders for their talks in Juncker's native Grand Duchy, said last week he has "no reason to be optimistic".

The European Parliament will this week vote on a resolution rejecting Johnson's demand that the backstop clause be stripped from the deal.

Johnson insists this measure, which temporarily keeps the UK in the EU customs union, has to be removed if he is to bring the agreement back to the House of Commons.

But the accord will also have to win the support of the other 27 EU leaders and the European Parliament if Britain is not to crash out with no deal on October 31.

Johnson said he would rather be "dead in a ditch" than ask his European counterparts to postpone Brexit for a third time.

"Be in no doubt that if we cannot get a deal — the right deal for both sides — then the UK will come out anyway," Johnson said, writing in the Daily Telegraph on Monday.

A UK spokesman said that Britain would refuse an extension even if one were offered.

Speaking to the BBC on Sunday, Brexit Minister Stephen Barclay indicated that any post-Brexit transition period could be extended past 2020 in order to resolve issues with the border.

Johnson, meanwhile, compared himself to Marvel comics hero Hulk, the rampaging mutant alter-ego of a mild-mannered nuclear scientist.

"The madder Hulk gets, the stronger Hulk gets and he always escaped, no matter how tightly bound in he seemed to be," Johnson told the Mail on Sunday.

Barnier will address the European Parliament session in Strasbourg on Wednesday as MEPs vote to reaffirm and reinforce the EU Brexit stance — and insist that the backstop must stay.

After his lunch with Juncker, Johnson is due to meet Luxembourg's Prime Minister Xavier Bettel. The pair will hold a joint news conference. — AFP