Finland and France want the UK to submit their written proposals for Brexit on September 30 at the latest or it will be "over", Finnish Prime Minister Antti Rinne said on Wednesday.

A Finnish official confirmed to Euronews the comments Rinne said to his country's media following a meeting in Paris on Wednesday with French President Emmanuel Macron.

"If the UK wants to discuss alternatives to the existing Brexit agreement then these must be presented before the end of the month," he told reporters.

"If no proposals are forthcoming, I believe quite a few European leaders agree with the position. Then it's over. Now is the time to come up with clear presentations and make them verifiable," he added.

That would give Boris Johnson, the embattled British Prime Minister, just 12 days to lay out his alternative proposals to the backstop arrangement — the insurance policy worked into the Withdrawal Agreement to prevent the erection of a physical border in Northern Ireland.

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Johnson has described the mechanism as "undemocratic" and wants its scrapped but although he and his team have said talks with Brussels have been "constructive," EU officials have stressed it expects the UK to come up with proposals on the issue.

"I told Boris Johnson that I have no emotional attachment to the Backstop. But I made clear that I do have an intimate commitment to its objectives. Invited the Prime Minister to make concrete, operational, textual proposals on alternative ways in which Backstop goals can be met," European Commission Jean-Claude Juncker told European lawmakers on Wednesday.

The bloc's chief Brexit negotiator, Michel Barnier, also said to lawmakers that "we need legally operational solutions" and that "it is not good enough to explain why the backstop needs to be removed."

The European Parliament voted yesterday to grant the UK another Brexit extension should it ask for it.

Johnson, meanwhile, has repeatedly said he wants the country out of the EU with or without a deal on October 31, a claim he has continued to make despite a bill passed by British lawmakers to prevent a No-Deal departure from the bloc.

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