West Ham have been named as the number one choice to move into the £429million Olympic Stadium.
The Barclays Premier League side are in pole position to move into the showpiece venue, but will not be able to take up residency until 2016-17 at the earliest.
Final commercial terms still need to be decided between the London Legacy Development Corporation (LLDC) and West Ham.
The LLDC board - which is tasked with sorting out the stadium's future - unanimously ranked the Hammers as the preferred bidder from a shortlist of four potential anchor tenants, ahead of rivals from Intelligent Transport Services in association with Formula One, UCFB College of Football Business and Leyton Orient.
The deal is not yet done and dusted as the LLDC is also working on an alternative use for the 60,000-seater stadium.
London mayor and LLDC chairman Boris Johnson said: "It will, if it goes through, mean a football legacy for the stadium but there is still a lot of negotiation still to go on between the LLDC and West Ham United about the terms of the deal.
"There is no dealbreaker as such. It is just a question of making sure that an asset which is a public asset and something that taxpayers put half a billion pounds into, that the value of that is properly reflected in the commercial deal that is now being done with a private sector entity.
"People will understand that my job is to get the best possible deal for the taxpayer."
A deal with West Ham would see the club move two miles from their 35,000-capacity stadium at Upton Park.
The club say the LLDC will get more money from naming rights and catering revenue if a football club takes over the venue.
Up to 100,000 tickets in a season, nearly 4,000 a match, could go to the local community as part of the club's package.
Retractable seating would have to be installed so there could be a quick change between athletics and football use and the club say their tenancy would help create 700 jobs.
Adding retractable seating and fully extending the roof on the venue will cost between £130million and £150million, on top of the £429million it cost to build the stadium.
For some time, there has been concern over a shortfall in the funding.
Kim Bromley-Derry, Newham Council's chief executive, said: "Currently £40million is the upper limit of our potential investment, subject to an appropriate and acceptable return on that investment and community benefits.
"Any change to that situation has to be considered by Newham's full council."
The original deal for West Ham to take over the stadium collapsed last year due to legal challenges from Tottenham and Leyton Orient.
There is still the fear of a fresh round of legal disputes over West Ham's occupancy, which is opposed by Orient chairman Barry Hearn.
Hearn told Sky Sports News: "One of the conditions of West Ham being named the first bidder is that it's cleared with the football authorities, that's a very key line.
"We believe that it's not been cleared with the relevant football authorities to the satisfaction of Leyton Orient and that not enough enquiry has been made as to the financial implications on Leyton Orient."
Hammers vice-chairman Karren Brady said: "On behalf of West Ham United, I feel privileged to have been granted the responsibility to play a key part in delivering a true Games legacy.
"I guarantee they will not be disappointed when our full vision for a stadium that is world-class in terms of supporter experience, sightlines and facilities is revealed. We will seek to share full details as soon as we are able to do so."
West Ham chairmen David Sullivan and David Gold issued a joint statement, saying the deal could be a key step in helping "move the club to the next level".
They said: "We are now committed to working with the LLDC in full consultation with our supporters to finalise our plans to make the stadium our home.
"We are ambitious for our great club and aim to set the benchmark for visiting away and neutral football supporters from across the globe to come and enjoy the iconic stadium and be part of our Premier League club experience."
An alternative plan for the venue includes a mix of cultural, sporting and community use.
Mr Johnson said: "We are very confident there is plenty of time to get the negotiations under way or either to go with plan B - lots of cultural events or sporting events.
"There are lots of operators coming forward to say how they could animate the stadium in a way that would draw huge numbers of people to the park.
"We have got plenty of time, we think, to get a football solution, if that is what we get in time for 2016/17."
LLDC chiefs would not be drawn on when a decision for a tenant for the stadium needs to be made.
The stadium is to be a multi-use venue which West Ham would rent for 25 days a year on a 99-year lease.
Pop concerts, community use and athletics, including the 2017 World Athletics Championships, are all set to take place there.
London 2012, the Olympic and Paralympic Games organiser, is due to officially hand over the stadium to the LLDC on December 14.