Speaking on his ‘Moggcast’ radio show , the arch-Brexiteer said the coup would probably happen after Parliament’s ‘meaningful vote’ on the Prime Minster’s Brexit deal.
Mr Rees-Mogg, who chairs the European Research Group of MPs pushing for a harder Brexit, submitted a letter of no-confidence in Mrs May last week, calling on others to follow suit.
His comments come as Downing Street confirmed Mrs May will meet European Commission president Jean-Claude Juncker for talks in Brussels on Wednesday ahead of a special EU Brexit summit on Sunday.
Despite confident predictions from the ERG that the threshold to trigger a leadership contest would be met early this week, so far an insufficient number of MPs have joined the plot.
“There are many people who lack confidence in the Prime Minister’s leadership and who have come to the conclusion that the deal or the proposal is very bad,” he said.
“Really much worse than could have been expected. As its been looked out carefully it’s turned out to be worse than the initial leaks rather than better.
“Some people don’t want a leadership vote now. They would like it when the meaningful vote comes up and think that is the time to put in letters.”
Mr Rees-Mogg also said that the Conservatives will be stuck with Mrs May as leader for the next general election unless they move to get rid of her now.
Predicting the outcome of the ‘meaningful vote’, Mr Rees-Mogg said it was ‘unlikely’ MPs would vote in favour of Mrs May’s deal, citing Tories including Dominic Raab who have said openly they will not back the deal.
He said: “In a way it is better that there has been this delay, though I can’t pretend that there has been some cunning plan, because we have allowed time for people to see the failures of the policy.”
Former Brexit minister and ERG member Steve Baker claimed last week that Brexit rebels had the 48 no-confidence letters required to trigger a leadership vote with a dozen to spare.
He later admitted this had been ‘inaccurate’, blaming MPs for misleading him.
26 MPs have announced openly that they have submitted letters to MP Graham Brady, who chairs the 1922 Committee of backbenchers.
If a no confidence vote does happen, it is still possible – some would say probable – that Theresa May would win thanks to the absence of a unifying figure to take over.