Sadiq Khan takes 20-point lead over Zac Goldsmith amid accusations of Tory 'Islamophobia'

Labour is on course to win its best result in the London Assembly ever

Labour Mayor of London candidate Sadiq Khan

The Conservatives’ London mayoral campaign has bled support in recent weeks amid accusations of dirty tactics and Islamophobic campaigning.

The latest poll of the contest by YouGov now shows Labour’s Sadiq Khan with a 20-point lead over Zac Goldsmith in the final round of the contest – 60 per cent to 40 per cent.

In the first round Mr Goldsmith is down five per cent on the previous poll, gaining just 20 per cent of the first round vote to Mr Khan’s 31 per cent.

Yesterday the Tories doubled down on their strategy of apparently trying to link Mr Khan, who is a Muslim, to extremists.

David Cameron at PMQs brought up Mr Khan having spoke on a platform alongside south London imam Suliman Gani, who he said supported Isis.

The Prime Minister was immediately criticised by Labour MP Chuka Umanna, who said Mr Khan was winning on bread and butter issues.

“So David Cameron has joined Zac Goldsmith's Islamophobic campaign against Sadiq Khan. Utterly disgraceful,” he said.

“The PM’s comments seek to shift the London Mayoral campaign from housing and transport – on which Sadiq is winning – to religion. Appalling.”

Mr Khan has long campaigned against Islamic extremism – having described it as a “cancer”.

Supplementary questions in YouGov’s poll suggest the public believe the Labour candidate would be better at fighting the ideology than Mr Goldsmith.

There is a close battle for third place in the capital between Ukip, who are on 7 per cent, the Green Party, who are on 6 per cent and the Liberal Democrats, who are on 5 per cent.

Respect candidate George Galloway is in zero per cent, according to the poll.

Labour are also on course to win their best result in the London Assembly ever, with a poll showing 45 per cent support in the regional list vote.

This result would be up from 41 per cent in 2012, which beat the previous record of 30 per cent in 2000.

The London Mayoral Election and London Assembly elections take place on 5 May this year, alongside other regional and local elections.