Work putting cables underground in Stratford has begun

Seb Coe, chairman of the organising committee, said it was a tough job, but achievements in the past 12 months had been "pretty remarkable".

"We've all the structures in place and the people we want in place," he said.

Meanwhile Olympics Minister Tessa Jowell has said "some aspects" of the budget - such as security - will rise.

Nearly a year on from London winning the bid to host the Olympic games in 2012, Lord Coe insisted the project was on schedule.

"It's been a good year, and there's been no complacency. But we will need every one of the 318 Mondays there are between now and the opening ceremony," he said.

It's a 24-hour-a-day job Lord Coe Work begins on 2012 venues

"Although there's a lot of work that has already taken place, it's a 24-hour-a-day job."

He said he had learned lessons from the much-maligned �757m Wembley project, currently running a year over deadline, as an MP debating where the stadium should go.

"We recognised it wasn't going to be a seamless process, but at least we knew where the risks were.

"We got the planning in place and the land acquisition, and we had the funding in place. Those three things were important."

Ms Jowell backed Lord Coe's confident predictions, adding: "According to the International Olympic Committee we are further ahead in our planning than any Olympic city has ever been. "

On costs, she told the BBC that reconfiguring facilities at the Olympic site in east London had saved about �500m over the past six months.

"Some costs will rise, other costs - as we have demonstrated with the Olympic Park reorganisation - will fall," she said.

"We won the bid on July 6 last year in Singapore and on July 7 London was attacked by terrorists.

"So obviously security after the 7th of July cost more than it was estimated to cost in the bid book."

The original Olympic budget - at 2004 inflation prices - was �1.5bn to run the Games, �560m for new venues, �65m on the athletes' village and �200m for security.