The claims led to renewed calls from construction union Ucatt for a public inquiry into the blacklisting scandal.

The Consulting Association’s Ian Kerr gave evidence to the Scottish Affairs Select Committee yesterday.

Kerr said that “Sir Robert McAlpine, Balfour Beatty and possibly Skanska” were involved in running checks on construction workers applying for jobs on the Olympics.

He also added that talks were held with contractors bidding for Crossrail work who were keen to avoid industrial relations problems which had dogged the Jubilee Line Extension project.

Steve Murphy, General Secretary of Ucatt, said: “There is an urgent need for a public inquiry into the blacklisting scandal.

“We need the full information, so that blacklisted workers can receive justice.”

Kerr also claimed that McAlpine helped set-up the Consulting Association with a £10,000 loan and paid his fine when he pleaded guilty to breaching data protection laws in 2009.

Sir Robert McAlpine said: “It is immediately apparent that the Consulting Association was established by a large group of construction companies and that Sir Robert McAlpine Ltd was not solely responsible for the establishment or the funding of The Consulting Association.”

Balfour Beatty said: “Mr Kerr raised a number of issues before the Scottish Affairs Select Committee yesterday, some of which are new to us.

“We are looking into these issues and will give our comprehensive response to the Committee when asked to do so.”

Dave Smith of the Blacklist Support Group said: “It has taken years of campaigning to get Ian Kerr  to spill the beans in public.

“I have a message for the supposedly respectable directors of multi-national construction firms, police officers and corrupt union officials who were all part of this conspiracy – get a good lawyer, because we’re coming after you next.”