Keir Starmer and Ed Davey have denied Conservative claims that Labour and the Liberal Democrats have formed a secret pact to inflict the hardest possible blow on Tories in Thursday’s local elections.

In a letter to Starmer, Tory chairman Oliver Dowden today accused the Labour leader of standing down candidates in “swathes of the country” where Lib Dems were the main challenger to Conservatives, while Sir Ed’s party was returning the favour where Labour was dominant.

For generations, the UK’s first-past-the-post electoral system has favoured Conservatives, who are generally able to stand as the sole major party of the right while the “progressive” side of politics is split between several candidates.

Mr Dowden’s letter appears to reflect concern in Tory high command that traditional Conservative voters may be flirting with a vote for Lib Dems on Thursday, and an attempt to scare them off with a warning that this would benefit Labour.

He said that Labour was standing candidates in just 61 per cent of seats in the Lib Dem heartland of the South West, compared to 97 per cent in 2018, while Davey’s party had candidates in 56 per cent of North East wards, down from 78 per cent four years ago.

And he said: “These shifts are far too substantial to be a mere coincidence... It now appears that your plans to deny the voters a proper democratic choice are coming to fruition.”

But Sir Keir told Sky News’ Sophy Ridge on Sunday: “There’s no pact. Everybody knows there’s no pact. We will put a candidate up (in Tiverton and Honiton) when there is a by-election after Neil Parish’s resignation yesterday.

“I think – and I’ll happily have this checked out - that we are standing more Labour candidates in this election than we’ve ever stood

“We’re very we’re out there. I’ve got teams working across the country, we’re positive, we’re laser focused on the cost-of-living crisis, and all you get from the government is mudslinging.

“Why aren’t they talking about the issue that matters? People are worried about paying their bills. What’s the government got say about that? Absolutely nothing, except `We’re going to tax you in the middle of a cost-of-living crisis’.”

Sir Ed told Ridge: “There’s no pact now. There’s not going to be a pact in the future. Liberal Democrats are actually fighting Labour in many areas – in Hull, in Sunderland in Sheffield in Haringey, in Southwark and many other places where there’s a real fight.

“These council numbers I think are a bit of a distraction and pretty desperate from the Conservatives. They always fluctuate from election to election, and actually Conservatives are fielding over 100 fewer candidates this time.”

Lib Dems have made no secret of the fact that they see their most fertile electoral territory in the so-called Blue Wall seats in the leafy suburbs, rural seats and commuter belts where traditional Tory voters are uneasy with the direction of the party under Boris Johnson.

Davey said: “Lifelong Conservative voters feel they are being taken for granted. They’re really worried about the cost-of-living crisis, alarmed that the Conservative response is to increase taxes on them. And it looks like Boris Johnson doesn’t care and doesn’t have a plan.

“Liberal Democrats are saying there should be a big tax cut for people and that is going down well. How that works out, I’m not sure but I do think we’ll make progress and I do think people are switching to the Liberal Democrats.”