Theresa May to trigger Article 50 in the last week of March

The House of Lords passed an amendment to the EU (Notification of Withdrawal) bill which called on the Government to bring forward proposals to guarantee unilaterally EU nationals' rights to remain in the United Kingdom within three months of triggering Article 50.

Jeremy Corbyn will lead a demonstration outside the Houses of Parliament on Monday (13 March) in bid to get MPs to vote in favour of unilaterally guaranteeing the residency rights of the more than three million European Union nationals in the UK.

May was forced to introduce the two-clause bill empowering her to trigger Article 50 after the Supreme Court ruled in January that she must seek parliament's approval to start Brexit.

"Our EU colleagues are not reassured by a government which tells them that deportation is not going to happen but declines to convert that assurance into law; some are anxious, some are desperate, some are already making plans to leave", the letter said.

Alistair Burt said he wanted the Brexit minister to offer a verbal guarantee that there will be a final vote on the Brexit negotiations, even if they fail to yield an agreement.

The upper house reviews and amends bills from the lower house.

The government has successfully defeated the two Lords amendments to its Article 50 bill.

Meanwhile, in the UK, Mrs May has scheduled a major Commons statement on Tuesday, raising Brexiteers' hopes she might use it to formally trigger Brexit.

The bill has already suffered two defeats in the House of Lords.

Mr Corbyn said: "We will keep on with this".

Tory rebel MPs backing the amendment may include ex-attorney general Dominic Grieve and Treasury committee chairman Andrew Tyrie.

The MP said Britain is ready if negotiations "go wrong" and demands are not met - but he expects "to get a good outcome".

Urging MPs to reject the Lords proposals, he told the Commons: "These amendments will undermine the Government's position in the negotiations to get the best possible deal for Britain and that can't be in the national interest".

Former Remain campaigner Baroness Brady has joined calls for peers to cede to the will of the Commons. The one thing I've learnt is you just can't operate effectively with one arm tied behind your back, ' she told The Sun.

"Bluntly, I'm reasonably sure where the political result will end..."

'That's exactly what the extra restrictions to the Article 50 bill proposed by Labour and the Lib Dems would do'.

Once Article 50 is invoked, Mrs May and European Union leaders have a maximum of two years to agree the terms of Britain's exit deal from the EU. The report suggests that she could take that opportunity to announce Article 50.

That would allow enough room to organise a special EU summit for 6 April, where EU leaders could approve negotiating guidelines for the European Commission and its Brexit negotiator Michel Barnier.