The Conservatives have taken the lead over Labour for the first time in over a decade, according to a new poll for the Telegraph newspaper.

The YouGov survey gives the Tories a two-point advantage over Labour - the first time the party has taken the lead for over a decade.

Conservative support is now at 37 per cent, an increase of one point since the end of May.

Labour support has fallen two points to 35 per cent following the Iraq intelligence row and last week's tax debacle.

The Liberal Democrats remain at 21 per cent, the poll suggests.

The survey gives the Tories their first poll lead - with the exception of a blip during the fuel protests - for 11 years.

Oliver Letwin, the shadow home secretary, told a Westminster lunch yesterday that the Tories had "turned a corner".

"I never thought that in my lifetime as a politician I would see the Conservatives in power, but I do now believe there is a possibility," he added.

The poll came as Iain Duncan Smith took his campaign into the inner cities, with a tour of Birmingham where he was accompanied by Rastafarian "peace officers".

Whilst the survey will be welcomed by the leadership it is unlikely to silence Duncan Smith's critics.

Several Tory backbenchers have expressed unease at his inability to land a punch on the prime minister during recent Commons exchanges.