Sadiq Khan has been accused of using “fake news tactics” after appealing for Liberal Democrat and Green voters to back him on May 6.

With just over a week until the London Mayor election, Sadiq Khan has urged Liberal Democrat and Green supporters to vote for him and has said that “a vote for any candidate other than me just increases the chances that my (Conservative) opponent sneaks over the line”.

Mr Khan said: “This election is a two-horse race between me and the Tory candidate. A vote for any candidate other than me just increases the chances that my opponent sneaks over the line and we wake up with a Tory mayor this May.

“Our city simply cannot afford for that to happen. The Tory candidate is actively hostile not just to the issues Liberal Democrat and Green voters care about, but to the modern, plural and progressive values that make London so special.

“That’s why I’m asking Lib Dem and Green voters to take into account my record over the last five years and to vote for London by lending me your vote.”

But the Labour mayor has been slammed by his Liberal Democrat opponent Luisa Porritt, who said that the comments were “an utter disgrace”.

Ms Porritt said: “It is an utter disgrace that a so-called progressive Mayor is engaging in fake news tactics to scare the public into voting for him in this election.

“Londoners backed a better voting system for our elections so they didn’t have to engage in this type of negative tactical voting. At a time when the Tories are threatening to abolish our proportional system, you’d think a Labour mayor would be out to defend it – not pretend it doesn’t exist.”

The comments from Sadiq Khan come just days after an ITV poll found that the gap between himself and nearest rival Shaun Bailey was narrowing, though Mr Khan still maintains a 13-point lead over his Conservative challenger.

Several recent polls have put Mr Khan on more than 50 per cent of first preference votes which, if repeated on May 6, would see him declared the winner without the need for a second round.

This will be the last London Mayor election to use the supplementary vote system whereby voters mark a first a second preference, following a Government decision to use the first past the post system from 2024 for all Combined Authority mayors and the Mayor of London.