A decision on the future of the Olympic Stadium faced fresh delay on Monday as the competition to find tenants was extended by eight weeks.
The group overseeing the process, the London Legacy Development Corporation (LLDC), said the delay is to allow all interested parties which registered enough time to properly prepare bids.
LLDC chief executive Andrew Altman said: "We are determined to run a process that is fair to all and delivers the best possible legacy for the Olympic Stadium.
"We have been very encouraged by the quality of the bids so far. However, a number of issues have arisen during the process and we believe it is sensible to give everyone more time so they can be addressed."
The LLDC said that it has been forced to make "a number of clarifications" to the bid process, as some potential bidders were put off by terms o the tender.
Governing body approvals, technical improvements to the stadium and the opportunity to bid for the right to exploit the stadium naming rights were among the controversial issues.
The aim is still to sign construction contracts for converting the stadium at the end of October and to reopen the venue in 2014.
It is hoped the extension will "make sure that there is a level playing field for all those who registered", a spokesman said.
"This is a significant public asset and a 99-year lease and it is right that we take the time now to get the best possible outcome for the stadium."
The £486m stadium was at one point awarded to West Ham United football club, but there are now four key bidders, the aim is to decide the eventual residents of the stadium before the beginning of this summer's Olympic Games.
There had been 16 would-be bidders who had shown an interest but this had dropped to four once submissions were made in March.