Prime Minister Theresa May has said it would “not be in the national interest” for a general election to take place before the UK leaves the European Union in March 2019.
Mrs May told journalists accompanying her to New York she was focused on delivering Brexit.
The next general election is not due until 2022.
But Labour has been demanding an earlier vote if MPs reject any deal struck between the UK and the EU.
At the weekend Downing Street dismissed a newspaper report of contingency planning for a general election, and Brexit Secretary Dominic Raab said the idea was “for the birds”.
Asked by journalists if she could promise there would not be an election before the UK leaves the EU, Mrs May replied: “What I’m doing is working to deliver a good deal with Europe in the national interest.
“It would not be in the national interest to have an election.”
Mrs May also told BBC political correspondent Ben Wright that any MPs thinking of voting against a deal she reached with the EU should “recall” their “duty” in delivering on the 2016 referendum result.
“I’m working to bring a good deal back from the EU,” she said.
“Members of the House of Commons, when they look at that deal and remember that we are delivering on the vote of the British people – that is what must be at the forefront of people’s thinking.”
The prime minister also reiterated her view that having no deal in place when the UK leaves the EU on 29 March 2019 would be “better than a bad deal”.
She said the government was doing the “right, sensible” thing in issuing advice for people to prepare for a no-deal scenario.