Ahead of an election expected later in 2024, the poll predicted Labour was on course to win 385 seats in parliament while the Conservatives will retain just 169, losing more seats than they did in 1997.

That would represent an 11.5% swing to Keir Starmer's Labour, the biggest collapse in support for a governing party since 1906, the newspaper said.

The 14,000 people surveyed by YouGov represented about seven times the usual number of people involved in the firm's polling. The survey was commissioned by a group of Conservative donors, the Telegraph said.

Recent polls have repeatedly shown the Conservatives trailing Labour. A YouGov poll in November put Sunak's party behind by 19 percentage points.

Asked about the latest forecast of a heavy electoral defeat, defence minister Grant Shapps said his party had a plan that would help win over voters.

"We have a plan, we're working to it. People will start to see the benefits of that," he told Sky News on Monday.

"That is why I think that we will wait until the election rather than relying on polls."

(Reporting by Sarah Young; Editing by William Schomberg)