A decision on the future of the Olympic Stadium faces fresh delay as the competition to find tenants was extended by eight weeks.
The London Legacy Development Corporation (LLDC) said it is to allow all parties that registered to receive the invitation to tender (ITT) additional time to submit a bid.
It is to allow more time to address a number of issues which have arisen since the ITT was issued in January, the LLDC said.
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.
"We want to make the process as competitive as possible and extending the competition period will allow all parties that registered an initial interest in the stadium another chance to bid."
The LLDC said it has made "a number of clarifications" to the ITT in response to issues that have arisen since it was first issued in January. Some potential bidders were put off by the original terms of 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.
"The fundamentals have not changed," Mr Altman 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."