Campaigning is set to heat up in Mid Bedfordshire, as both Labour and the Liberal Democrats bid to take Nadine Dorries’ former seat after she quit the Commons.

The former culture secretary finally handed in her resignation over the weekend and is expected to leave her parliamentary seat on Tuesday, after notifying the Chancellor of her intention to do so on Saturday.

Jeremy Hunt is expected to trigger her exit from the House of Commons under the archaic process of appointing her to be Steward and Bailiff of the Three Hundreds of Chiltern.

This will mean a motion called a “writ” can be moved when Parliament returns on September 4, giving between 21 and 27 working days for a by-election to be held in Mid Bedfordshire.

Labour and the Lib Dems are already campaigning for the seat, with Prime Minister Rishi Sunak facing the prospect of another difficult electoral test in a nominally safe constituency.

Liberal Democrat leader Sir Ed Davey will visit Mid Bedfordshire later on Tuesday, his fourth campaign stop in the seat since Ms Dorries originally announced her plan to depart and the first since she formally stood down.

While there he will call for increased funding to expand capacity at local GP practices.

“The people of Mid Bedfordshire have been taken for granted for too long,” Sir Ed said.

“From not being able to see a GP to having an absent MP, it’s clear this part of the world has been completely ignored by the Conservatives.

“People across Bedfordshire should be able to get an appointment with their doctor when they need it, instead we have a Government that just can’t get the basics right.

“The Liberal Democrats are the clear challengers in this by-election, every vote for our local champion Emma Holland-Lindsay will be a vote to send a message to the Conservatives that enough is enough.”

Labour’s candidate Alistair Strathern was also campaigning over the bank holiday weekend.

The party is seeking to overturn a 24,000 majority in the seat to see off the Tories.