9:20AM Lemley reveals the real reasons for his departure from the ODA, including delays and politics

Jack Lemley, who last week resigned as chair of the Olympic Delivery Authority, said he left because there was a strong chance the project would go well over budget. Lemley also cited slow progress on the programme and political squabbles.

The revelations came in an interview with a local newspaper in his hometown of Idaho, where he has returned to continue to lead his construction consultancy Lemley Associates.

Lemley told the Idaho Statesman: “I went there to build things not to sit and talk about it.” He said didn't want to wreck his reputation for delivering projects on time and on budget, so he “felt it was better to come home now than face that in five or six years.”

The original bidding documents for the 2012 Olympic project put the cost of the building programme at around £2.3bn but some sources have suggested the final price tag could be closer to £6bn.

Lemley criticised the plan to shrink down the Olympic stadium from an 80,000-seat athletics venue to a 25,000-seat football stadium. “A football field is not compatible with an athletic stadium.”

He also said the process of negotiating with local businesses in order to clear them off the Olympic site had hindered the pace of the project. “Some of them were happy to move, and some of them weren’t. In any event there was a huge amount of local politics.”

Lemley’s official statement last week said: “It has been a privilege to chair the ODA for the last year and lead the organisation through its formative stages. The delivery partner has been appointed and the ODA is ready to move to the next stage of its development. I am keen to return to the helm of my international construction consulting firm in America, which is increasingly busy with major contracts.”