The decision on who will take residence in the Olympic Stadium after the 2012 Games has been delayed.
West Ham United and Tottenham were due to learn on Friday whether their bids had been successful.
But the board of the Olympic Park Legacy Company has asked for more time to discuss the merits of both and there may now not be a final ruling until the end of March.
Both clubs handed in their bid proposals for 60,000-seat arenas last Friday. West Ham said they would provide the legacy for athletics as they would retain the running track in Stratford.
Spurs, by contrast, insist it makes no financial sense to have a track at a football stadium and are prepared to knock the venue down and start again from scratch.
In a statement the OPLC said today: "Given the detailed nature of both bids received, we need more time to seek further clarification with both bidders in order to identify a preferred bidder. The Stadium is a significant public asset and we have a duty to run a robust process.
"Securing the most appropriate solution for the Stadium is vital to our long-term aspirations for the future Queen Elizabeth Olympic Park and the wider regeneration of the area.
"In addition to the two shortlisted bids, the Legacy Company also has the option of the original plan to convert the Olympic Stadium to a 25,000 seats, mixed-use venue. In going to market, the Legacy Company's aim was to consider options which would enhance and build on that plan."
