"She said that she did not intend to lead us into the 2022 election", lawmaker Alec Shelbrooke said, adding "her opening remarks were, "I am not going to hold a snap election".
The prime minister won the confidence vote with a majority of 83 - 63% of Conservative MPs backing her and 37% voting against her.
Mrs May had earlier acknowledged that major progress was unlikely at the two-day summit, even as she tried to get tweaks to the withdrawal package that she could use to win over opponents - particularly pro-Brexit politicians whose loathing of the deal triggered a challenge to her leadership this week.
May's leadership remains precarious and she is still at risk of being toppled, say Conservative party insiders.
The EU says it will not renegotiate the backstop, but may agree to give greater assurances on its temporary nature.
"It will be impossible to break open the negotiated Withdrawal Agreement".
May said: "We will be holding talks in coming days about how to obtain the further assurances that the UK Parliament needs in order to be able to approve the deal".
"If the backstop has an expiry date, if there is a unilateral exit clause, then it is not a backstop", said Irish Prime Minister Leo Varadkar.
However, her remarks contradict reports that European Union leaders are unwilling to renegotiate the deal already agreed and are instead of calling on British MPs to be "responsible" ahead of the parliamentary vote now pencilled in for 14 January.
The EU also fear giving May assurances now would see her return in the new year seeking further concessions.
On each occasion, the European Union simply made a decision to ignore the vote; either it pressed ahead with ratification in other states so that the countries in question were forced to vote a second time (Denmark and Ireland) or the same legislation was passed by the political class in their respective national parliaments (France and the Netherlands) and against the people's wishes.
Liam Fox, the global trade minister, said Thursday the Cabinet could block May from bringing her exit withdrawal deal before the House of Commons next month and that it might insist Britain's scheduled departure date of March 29 be moved back several months to provide time for a fresh approach.
Labour leader Jeremy Corbyn said: "It is clear there will be no changes to the deal the Prime Minister brought back last month".
But when May took it home, she ran into renewed opposition from hardline Brexiteers in her Conservative party and this week she baulked at putting it to a vote in parliament. The same thing is now happening against Britain, and we are now witnessing, in real time, a sixth attempt to strangle democracy.
"I think the government will have to lose several votes", he said.
DUP deputy leader Nigel Dodds said his party, which helps keep Mrs May in power, was still concerned about the Irish backstop plan, which most MPs were against.
"It's fatal to make predictions but I do think December, January, February, March, this [Brexit] crisis will continue".