Artisan took out £1.4m before selling Bickerton

The two men involved in the transaction were Stephen Dean, chairman of Artisan, and John Aviss, who bought Bickerton and a second firm, Driver Construction, through his Infiniteland holding company.

An Artisan insider said Driver and Bickerton's net asset values were each reduced by about £1.4m before the sales. He added that both were carried out legitimately.

Dean confirmed that Artisan had taken money out of Bickerton, but refused to say how much.

Aviss was unavailable for comment.

It was also revealed this week that two projects that Bickerton was undertaking for Artisan ran into difficulties after the sale. One was a job in Watford, where Artisan did not pay it the full amount owed. The other was an £8m refurbishment project at the Old Glasshouse building close to Bickerton's offices in St Albans. This was part of Bickerton's future order book but was stopped after the deal was signed.

Artisan finance director Chris Musselle denied that Bickerton's collapse was caused by the payment dispute and the lost contract. He said: "They did not contribute to the downfall of Bickerton in a significant way."

A second strand to the relationship between Dean and Aviss involves Mea Corporation, an M&E engineer owned by Aviss that is being investigated by the Serious Fraud Office.

The original agreement between the two was that Bickerton and Driver would be bought by Mea. This fell through after Mea went into administration, but Dean said Aviss had given him a binding guarantee that he would buy the companies, so had to go through with the deal.

In a separate development it has emerged that Dean had a plan to float Mea before it was liquidated, through a holding company. Dean subsequently pulled out of the deal. He said: "It did not get past first base."