Nicky Morgan has urged fellow politicians to stop "setting about" the leadership of the Conservative Party.
Appearing on the breakfast show with Julia Hartley-Brewer, Ms Morgan said it would be the "height of self-indulgence" to trigger a leadership contest.
"We had a confidence vote which was engineered by those who are particularly in favour of Brexit, and that was won by the Prime Minister," she said.
"It would be the height of self-indulgence by members of the party to be focussing and setting about the leadership, to trigger a leadership contest and everything else when we've got elections, we've got plenty of other issues that need to be addressed in the country and we have got to get this first phase of Brexit sorted."
The MP's appearance on the breakfast show followed the news that senior Conservatives ruled out changing the rules to allow an early challenge to Theresa May's leadership.
"I don't think changing the rules in the heat of a moment to deal with a particular situation sets a good precedent for the future," Ms Morgan added.