Peers in the House of Lords are confident they can force changes to the Article 50 Bill and derail Theresa May’s timetable for starting Brexit.

The Independent has learned of the areas of the legislation that Labour peers are determined to amend – the rights of EU nationals, the vote on the final deal and regular reports on the exit talks.

The Liberal Democrats will also go into battle over EU nationals and other attempts to re-shape Brexit are certain to come from independent crossbenchers.

The stance puts the Lords firmly on a collision course with the Government, which has demanded that the upper chamber “get on and deliver the will of the British people”.

Immediately after the Commons passed the Bill – unamended – a Government source threatened: “The Lords will face an overwhelming public call to be abolished if they now try and frustrate this Bill.”

Ms May is thought to want the Bill to receive Royal Assent on March 8 – allowing her to formally notify the EU that she is invoking Article 50 at an EU summit later that week.

But any amendments to the Bill will force the Prime Minister to wait at least another week, while still allowing her to achieve her original target of the “end of March”.

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A Labour source in the Lords said: “We believe we can find a way to get the Lords behind us to push the Bill back to the Commons for another go at changing it.”

On the touchstone issue of EU nationals, specifically, he added: “We are optimistic that, if this has to be pressed to a vote, the numbers will be there.”

That confidence was echoed by Dick Newby, the Lib Dem leader in the Lords, who said: “We believe we have support on all sides to deliver on the promises the Government should have made to millions of people who have made our country their home.”

The European Union (Notification of Withdrawal) Bill reaches the House of Lords on 20 February, when no fewer than 150 peers are expected to try to speak in a two-day debate.

Labour will attempt to persuade – or force – the Government to think again over:

* An immediate, unilateral guarantee that the rights of 3m EU citizens in the UK will be protected after Brexit.

A threatened Tory rebellion in the Commons evaporated when Amber Rudd, the Home Secretary, insisted “nothing would change” without MPs’ consent.

However, that still means the uncertainty facing EU citizens will continue unless and until Ms May agrees a deal with EU leaders when the exit talks get underway in April.

* A written guarantee that Parliament will be given a “meaningful” vote on any final deal that the Prime Minister secures – and, crucially, if she fails to agree one.

In the Commons, Keir Starmer, Labour’s Brexit spokesman, claimed victory when ministers conceded a vote before the European Parliament starts its consideration, probably in late 2018.

But the assurance was verbal only. The source said: “We want it on face of the Bill and written into the legislation.”

* Regular updates to Parliament on the progress of the Article 50 talks – at least every three months.

An amendment demanding reports every two months was thrown out in the Commons after a minister branded it “dangerous”, because it might allow further interference by the courts and delay the negotiations.