The Conservatives could be in danger of losing more than a dozen seats in their so-called “blue wall” heartlands, a new poll suggests.

YouGov found that voting intention in 53 such constituencies in the south and east of England currently held by the party stood at 44% for the Conservatives, 24% for Labour, 18% for the Liberal Democrats and 9% for the Greens.

“The Conservatives could be set to lose up to 16 seats in their ‘blue wall’ heartlands if an election was held tomorrow,” research manager Patrick English said.

He said the voting intention figures represent “a change of minus eight for the Conservatives from their 2019 performance in these constituencies, plus four for Labour, a surprising six-point drop for the Liberal Democrats, and a sizable seven-point gain for the Greens”.

Mr English added: “The Conservatives are falling almost twice as fast in the blue wall as they are nationally, with the latest YouGov poll showing them five points down on their 2019 general election showing.”

Those surveyed for the research expressed concerns about the government’s handling of Brexit and the need for people to have their say on local housing developments.

All of the seats voted Remain in the 2016 EU referendum and have a higher-than-average concentration of university degree holders.

Boris Johnson currently has a Commons majority of more than 80, with the Tories taking a number of traditional Labour “red wall” constituencies in 2019 on the way to the party’s best election result in decades.

That success means the party would have to lose a number of seats elsewhere, in addition to any “blue wall” reverses, in order to see its status as the largest party in parliament evaporate.

Some have suggested the prime minister has been preoccupied with shoring up Tory support in the former Labour heartlands it now holds, at the expense of traditional Conservative constituencies.

Others say such talk is wide of the mark, but the result of the recent Chesham and Amersham by-election offers potential evidence there could be something in such claims of cracks in the “blue wall”.

YouGov said its findings suggest that particular result was “no isolated incident”.

The Conservatives won the seat at the last general election in 2019 with a majority of more than 16,000.

But this was overturned by the Liberal Democrats, who won the constituency by 8,028 votes in what was a stunning result.

“If the swings were uniform across all constituencies, Labour would be set to gain a total of nine blue wall seats and the Liberal Democrats three,” Mr English said.

“While it would not be anywhere near enough to offset the party’s losses in the so-called red wall in 2019, Labour punching holes in traditional Tory foundations will send alarm bells ringing across Conservative Associations and MPs in the south.”

YouGov said its findings suggest that constituencies such as Chingford and Woodford Green (represented by former cabinet minister and party leader Iain Duncan Smith), Chipping Barnet (currently held by former cabinet minister Theresa Villiers) and Wycombe (represented by prominent Brexiteer and former minister Steve Baker) could change hands.

“A large drop in the Conservative vote share would also severely threaten four other Tory constituencies, including current Foreign Secretary Dominic Raab in Esher and Walton as well as Cambridgeshire South, Cities of London and Westminster, and Guildford,” Mr English said.

YouGov polled 1,141 adults between 20 and 28 July.