London 2012 organisers face the toughest economic circumstances outside of a state of war to put on the games, an influential member of the International Olympic Committee said.
Kevan Gosper, an Australian who is head of the IOC's press commission, made the warning to London 2012 chairman Sebastian Coe at a question-and-answer function in the capital yesterday.
Mr Gosper, a vice-president of the Sydney Olympics organising committee, said: "I think you and your team face the toughest time - short of war-time - to get the project to 2012."
Lord Coe responded by saying the games could help London and Britain cope with a recession.
"More than 3,500 people are on the [games] building site currently, of which 10 per cent had been permanently unemployed. The work safeguards these jobs in an economic downturn," he said.
"Billions of pounds of contracts are available, so this is a very good project to be having at the moment.
"No one would have chosen this [downturn], but the games could account for 6-7 per cent of economic activity in this city over the next five years, not to mention the impact it could have on other parts of the country.
"That's why we should be on the front foot - in good times or in bad this is a project that really has an extraordinary impact."
IOC president Jacques Rogge also warned the financial crisis poses a challenge for organisers but is confident the games will survive the test.
Mr Rogge said the games had survived global economic slumps in the past and pointed out that London will be less dependent on the huge building projects than Beijing.
In his speech to the Royal Society of Arts, Manufactures and Commerce, Mr Rogge said: "I am conscious that we come out of the enormous success of Beijing, into difficult economic times.
"Well, the games have survived difficult times before.
"They have survived and thrived because of what they mean to people all over the world. The games remind us that the transient difficulties of life can be overcome through hard work and determination."
International Olympic chiefs are in London this week for four days of talks on the lessons that can be learned from the Beijing games.
Officials from Beijing are sharing their experiences with organisers from London, Vancouver, Sochi and the 2016 candidate cities.
In his speech Mr Rogge said the IOC's decision to slim down the games following the Olympic Games Study Commission report of 2003 would help London to cope with economic difficulties.
He added: "This report made a series of recommendations to limit the size, cost and complexity of future Olympic Games.
"London has learned from this, and it will build its games around legacy and sustainability.
"It will use existing and temporary venues, and the city's existing infrastructure. It will only build facilities that will be valued and used by the local community long after the games are over. London has made regeneration a priority.
"Each games are unique. It is not the amount of money spent that determines how good a games is, it is also the unique and inspiring atmosphere created within the city. I'm sure London will do very well there."
Mr Rogge also praised the record-breaking medal haul of the British Olympic team in Beijing and said the challenge now was to inspire a generation of couch potatoes to take up sport.Reuse content