The Keltbray managers, Michael McCarthy, Simon Lacey, and John Burke, were convicted of receiving the bribes, which represented a ‘breach of trust’ in their obligations to Keltbray.

Southwark Crown Court also found Arben Hysa, the owner of specialist demolition contractor Tony Demolition Workers (TDW), guilty of handing out kickbacks over a period spanning December 2012 and June 2018 to ensure his workers were used on Keltbray projects.

Tony Demolition Workers benefited from Keltbray specialist labour contracts worth £15m, including work connected with the redevelopment of Battersea Power Station.

The Keltbray employees involved were dismissed in 2018 when the details of the offences first emerged.

Cathrine Williams, a solicitor, who allowed her bank account to be used by her partner Burke was found not guilty of money laundering-related offences.

Andrew Cant from the Crown Prosecution Service said: “McCarthy, Lacey, and Burke ignored the rules in respect of their obligation to act in the interests of their employer Keltbray when dealing with external contractors by accepting significant sums of money from Arben Hysa.

“Williams, a solicitor, allowed her bank account to be used by Burke to receive the bribes.”

“The CPS will now commence confiscation proceedings in order to reclaim the ill-gotten gains of the defendants’ crimes.”

A spokeswoman for Keltbray said: “This outcome reinforces our commitment to accountability and upholding the highest standards of conduct across our business.

“The verdict reflects the values outlined in Keltbray’s Code of Conduct, and emphasises the importance of our immediate dismissal policy, which was applied at the time of the incident.

“We are pleased to bring this matter to a close and remain focused on maintaining a culture of integrity and respect within our organisation.”

Sentencing will take place in April.