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Number 10 has accepted Labour's attempt to force the prime minister to publish a plan for Brexit before Article 50 is triggered, the BBC has learned.

Shadow Brexit secretary Keir Starmer put forward a motion for debate on Wednesday calling for details of the strategy, with support from some on the Conservative back benches.

Now the government has tabled an amendment to win them back.

But sources are not committing Theresa May to publish any specific plans.

The motion will still be debated on Wednesday as part of the Opposition Day debate offered to rival parties to choose their subject for discussion in the House of Commons.

Mr Starmer tabled the motion, which said Mrs May should commit to publishing the plan for leaving the EU before Article 50 is invoked because it was "Parliament's responsibility to properly scrutinise the government while respecting the decision of the British people to leave the European Union".

The motion received the backing of some Tory MPs, with pro-European figures like Anna Soubry pledging their support.

But now, government sources have told BBC political editor Laura Kuenssberg that an amendment has been put forward by Downing Street, agreeing to publishing a plan, in exchange for a commitment to invoking Article 50 before the end of March 2017.

Steve Baker, Conservative MP for Wycombe, tweeted pictures of the amendments, claiming they also have the backing of the DUP and Douglas Carswell, UKIP's only MP.

Image copyright Steve Baker

However, government sources would not confirm any specific form of document on any specific timetable to fit with the commitment to publish a Brexit plan, apart from saying that it will be before Article 50.

Sources also said by accepting Labour's amendment, the government was not agreeing to give MPs a vote before the process of leaving the EU begins.

Mr Starmer, who will lead the debate for Labour, called the amendment "a welcome and hugely significant climbdown from the government" and said his party would push for the Brexit plan to be published by January.

"For the last two months Labour have been pushing the government to put their plan for Brexit before Parliament and the public," he said. "Without that plan, we have had unnecessary uncertainty, speculation and a running commentary on the government's likely approach. Labour will hold the government to account on this."

Ms Soubry, a Remain campaigner and Conservative MP for Broxtowe, added that the new amendment was a "significant victory".

She told the BBC News Channel: "We're moving in the right direction, which is that Parliament should have these debates and Parliament must trigger Article 50. The government need have no fear - we will vote to leave the EU because we have accepted the result of the referendum. But now we need to get the very best deal for our country."

Earlier, EU chief negotiator Michel Barnier said the UK would have to reach a Brexit deal by October 2018. He said time would "be short" for negotiations because the proposed deal needed to be ratified by the European Council and European Parliament as part of the two-year process set to be triggered by Article 50 being invoked in March.