Senior Conservatives have attacked their own party's "outrageous" campaign for London mayor.

The bitter recriminations came as the party faced almost certain defeat in the race to replace Boris Johnson.

The Tory campaign has been dogged by allegation of racism for weeks.

The candidate Zac Goldsmith has faced claims that he was ‘dog whistling’ to voters in a bid to highlight the fact that his Labour opponent Sadiq Khan is Muslim.

Andrew Boff, the Conservative leader of the Greater London Assembly, was among those who slammed his own party’s negative tactics.

Mr Boff said that the Tory campaign’s relentless focus on Mr Khan's alleged links to “extremists” could hit community relations.

And he warned that the party faced being punished for the tactics at the ballot box.

Mr Boff said of the Tory strategy: 'It was effectively saying that people of conservative religious views are not to be trusted and you should not share a platform with them.

“That's outrageous.”

He accused Mr Goldsmith of doing “real damage” and said he had “blown up bridges" that the Conservatives had built with London's Muslim communities.

He added: 'I do believe it's going to affect Conservatives at the sharp end, especially in those parts of London where there is a high Muslim population.'"

His blast came before counting had even begun in the battle for City Hall.

But the Tories have been facing a backlash for weeks, with Mr Khan zooming ahead in the polls.