Gordon Brown has pledged that the London 2012 Games will be on time and on budget while visiting the Olympic Park for the first time.
The Prime Minister made the trip to east London on the third and final day of the International Olympic Committee (IOC)'s inspection visit as building work for the stadium began three months early.
There is a "determination" to keep a tight rein on the £9.3bn budget and to garner public support for the event, according to Mr Brown. He said: "I think that what people do want to know is that it is on budget and on time."
"We already started building this stadium three months ahead of schedule. It is plain that people such as the Olympic Delivery Authority (in charge of Olympic venue and infrastructure) are determined to come in on budget and on time."
He predicted the stadium would not be a white elephant, declaring it a "world-class stadium that will leave a world-class legacy for the future and we believe that this will be a world-class Olympics that we will organise".
Mr Brown said that 75p of every pound will be spent on regenerating the area so that "this stadium, unlike other Olympic stadiums, will be used every day of the year" after the Games.
Visiting the site Denis Oswald, the IOC's co-ordination commission chairman, said: "The Olympic stadium is the heart of the Games and of course when you start preparing for the Games you do a lot of thinking, writing and drawing plans - it is not really anything spectacular.
"Then one day you see something coming out of the ground and something concrete and you realise the Games are taking shape.
"We can see the stadium emerging and what it is going to be and therefore it is a very good coincidence that the committee have the chance to come to the Olympic Park."
Mr Oswald also threw the IOC support behind London's preparations for 2012, saying: "The Games are in very good hands in general and we are very happy with the preparations."
