British Prime Minister Theresa May avoided a major upset in the House of Commons on Tuesday after lawmakers rejected a series of proposed amendments to her Brexit blueprint.

One of the key amendments handed down from the House of Lords, the upper house of parliament, would have granted lawmakers the power to reject the Brexit deal and force the government to return to the negotiating table just months before the UK is slated to leave the EU next March. 

However, the government narrowly defeated the bid with the House of Commons voting 324 to 298 against the amendment — albeit only after May agreed to a series of last-minute concessions with pro-EU rebels inside her Conservative Party. 

As part of the deal, May promised to make changes to the EU withdrawal bill to give parliament more powers in the Brexit process. According to local media reports, the prime minister is prepared to adopt a section of the proposed amendment so that, if there is no agreement on Brexit between the UK and EU by November 30, MPs will have the chance to vote on a motion stipulating what should happen next. 

That change greatly reduces the chances of the UK crashing out of the EU if it doesn't like the divorce terms being offered by Brussels.

"I am quite satisfied that we are going to get a meaningful vote on both deal and no deal," pro-EU Conservative Dominic Grieve said. "I have no doubt about it after today."

Other amendments nixed

Parliament also voted against challenging the government's plan to set March 29, 2019 — or "Brexit Day" — into law.

That date is precisely two years after the triggering of Article 50, a statement of intent for leaving the EU, which says it should be achieved within 24 months.

Another vote, on where the UK must commit to guaranteeing a frictionless border between Northern Ireland and the Irish Republic, was set to take place later on Tuesday.

'Message to Brussels'

A spokesman for May said the prime minister told her Cabinet ahead of the Commons vote that it was "important in terms of the message they send to Brussels" and that "anything which undermines the government at home would make the negotiations with the EU more difficult."

Brexit Secretary David Davis told the BBC on Tuesday morning that, whatever the outcome of the vote, parliamentarians would not have the power to reverse Brexit. "Whatever we do, we're not going to reverse that," Davis said. "A meaningful vote is not the ability to reverse the decision of the referendum."

Read more: EU Brexit negotiator Michel Barnier doubtful of UK backstop proposal for Irish border

Junior minister Phillip Lee resigns hours before vote

Defeat for May would have marked another blow to her already weakened authority. The prime minister has struggled to stave off both pro-EU rebels within her party, and euroskeptics pushing for a more complete break with Brussels.

he deep rifts within May's Conservative Party were once again laid bare just hours before the vote, after a junior minister at the Justice Ministry resigned in protest over what he described as the government's "wish to limit" parliament's role in shaping Brexit.

Phillip Lee, an outspoken critic of Brexit, said in his resignation letter that Tuesday's vote was a choice between "bad and worse" options.

"I cannot support the government's decision to oppose this amendment because doing so breaches such fundamental principles of human rights and parliamentary sovereignty," he said, adding that he would vote against the prime minister later on Tuesday.

Read more: 'Armageddon' Brexit: 'No deal' scenario could hit fuel and food

"If, in the future, I am to look my children in the eye and honestly say that I did my best for them I cannot, in all good conscience, support how our country's exit from the EU looks set to be delivered."

Last year, Lee had called on the government to release its economic impact assessments of Brexit. The government refused, but its analysis was eventually leaked to BuzzFeed News in January. It asserted that the UK would be worse off after Brexit in every scenario, the only question being by how much.

Trading ties up for debate on Wednesday

British parliamentarians are set to discuss on Wednesday a series of other amendments tabled by the upper house, mainly concerning Britain's post-Brexit trading relationship with the EU. 

The most significant proposal is for the UK government to make remaining a part of the European Economic Area (EEA) — and therefore stay within the EU single market — a negotiating objective. 

However, it is expected to fall in Wednesday's vote because, like May, the leadership of the opposition Labour Party is also against it. Party leader Jeremy Corbyn has called on his ministers, most of whom would support the motion, to abstain.

Read more: UK establishment fighting 'proxy war' against Corbyn

"The Norway model [the term often used to describe EEA membership while outside the EU — the ed.] does not reflect the needs of the much larger British economy. It would mean taking rules from Brussels, but having no role in making them," Labour leader Jeremy Corbyn said in a Facebook post. "Labour will only vote for a final Brexit deal if it delivers a strong relationship with the Single Market based on full tariff-free access and ensures no loss of rights and standards."

dm/msh (AP, Reuters, AFP, dpa)

Each evening at 1830 UTC, DW's editors send out a selection of the day's hard news and quality feature journalism. You can sign up to receive it directly here.