LONDON (Reuters) - Prime Minister Theresa May defused a rebellion in parliament over her Brexit plans on Tuesday but only after having to compromise and hand lawmakers more control over Britain’s departure from the European Union.

After winning Tuesday’s ballot over changes to a future “meaningful vote” on a final agreement with Brussels in her EU withdrawal bill, May’s plans to end more than 40 years of membership in the bloc were still on track.

Her concession to discuss the changes may mean lawmakers could have more power if she fails to secure a Brexit deal, possibly leading to a softer approach to Britain’s divorce. However, as things stand now, they will not be able to send the government back into negotiations if they reject an agreement with the EU.

Brexit campaigners still voiced concern that the concession may open the door to the EU trying to force Britain into retaining the closest possible ties with the bloc by weakening the government’s hand in the talks.

Pro-EU lawmakers, however, welcomed it as a signal that the government was moving towards ruling out a hardline “no deal” Brexit.

For now, May saw off a revolt that would have challenged her authority at a time when she is increasingly under pressure to move ahead with all-but-stalled Brexit talks in Brussels by offering a more detailed plan.

The pound traded higher against the euro and the dollar after the votes.

Brexit minister David Davis had earlier warned lawmakers that the government would never allow them to “reverse Brexit” or undermine negotiations.

After the vote, a Brexit department spokesman said: “We have not, and will not, agree to the House of Commons binding the government’s hands in the negotiation.”

The government’s victory was the first major win in two days of debates on its EU withdrawal bill, which will sever ties with the EU, after the upper house of parliament, the House of Lords, introduced 15 changes.

It followed a strained parliamentary session, where the deep nationwide divisions opened up by Britain’s vote to leave the EU in 2016 were on display, with pro-EU lawmakers saying they had received death threats.

CONCESSIONS

In a tense atmosphere where it was not clear which way the vote would go, the government secured its victory only after offering concessions to one of the leaders of a group of Conservative lawmakers who were threatening to vote against May.

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An hour before the vote, the government’s solicitor general, Robert Buckland, promised lawmaker Dominic Grieve talks on increasing the powers of parliament if May was unable to reach agreement in Brussels. The two then discussed a deal in whispers as other lawmakers made speeches around them. It was sealed at a private meeting between May and potential rebels.

Buckland indicated the government would look into the possibility of adopting Grieve’s push for ministers to secure parliamentary approval for their Brexit plans if they fail to negotiate a deal with the EU. It paid off.

“I’m quite satisfied that we are going to get a meaningful vote on both ‘deal’ and ‘no deal’,” Grieve told Sky News.

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But the latest manoeuvre by a minority government that has been forced to compromise with parliament worried some lawmakers who feared it would hand the EU an incentive to withhold any agreement on an exit deal to force a “softer” Brexit.

“This needs to be resolved,” Andrew Bridgen, a pro-Brexit Conservative lawmaker, told Reuters.

The Labour Party’s Chuka Umunna, who backed staying in the EU, welcomed the concession as the end of the government threatening to allow Britain to crash out of the EU without a deal.

KICKING DOWN THE ROAD

Earlier, May appeared to have also stemmed a rebellion on Wednesday over her commitment to leaving the EU’s customs union which will transform Britain’s trading relationships for decades to come.

But her parliamentary problems will not stop there. Rebels have said they will challenge May’s plans to leave the customs union during votes on other bills, on trade and customs, which will be brought back to the house some time before July 24.

There is little May can do. After losing her party’s majority in parliament at an ill-judged election last year, she now relies on the support of a small Northern Irish party and the distance between victory and defeat is narrow.

Often she simply puts off votes that could end in embarrassing defeats.

But as time ticks by, she can no longer kick decisions down the road, increasingly under pressure from EU negotiators to come up with detailed positions not only on customs, but also on the wider trade agreement and governance.

The EU is expecting her to have made progress by a summit in June and both sides want to reach a deal by October.

In a day of drama, May’s position seemed suddenly weaker when junior justice minister Phillip Lee, who has long been critical of Brexit strategy, resigned and said he would vote against the government.

Labour’s Brexit policy chief, Keir Starmer, said May had been forced to avoid a “humiliating defeat” and “to enter negotiations with her backbenchers”.