London 2012 organisers have been urged to be up front about how many tickets will be available for the Olympics and how much they will cost.
The London Assembly's economic development, culture, sport and tourism committee said the public needed to have faith in the ticketing system.
Games organisers said details would be revealed after the Paralympic Winter Games in Vancouver had finished.
There will be 9.2 million seats available during the event.
The committee has written to London 2012 chiefs requesting details on how they plan to fill seats at the Games.
'Open and transparent'
Committee Chair Dee Doocey said: "The key issue is simple: How many people will be ahead of the average Londoner in the queue for Olympic tickets?
"Locog - London Organising Committee of the Olympic Games - needs to be open and transparent about how many tickets are going to be available for the public and how many are going to be reserved for the Olympic family.
"These tickets for International Olympic Committee staff, officials, partners and sponsors will significantly reduce the number of seats available for the public."
The committee said it would like to know how many tickets will be available at less than £10, £20 and £30 and how they will be shared out among the events.
Other questions included how any possible stand-by scheme for unused tickets might work and who, if anyone, would count as a priority group for preferential or low-cost tickets.
London 2012 should publish its ticketing strategy in draft form as soon as possible to allow the public to comment on it before it is finalised, the committee advised.
Tickets for the Games will not go on sale until 2011, according to Locog.
A London 2012 spokesman said: "We will be making an announcement about our ticketing strategy after the Vancouver Paralympic Games has finished."
The 2010 Paralympics is scheduled to finish on 21 March.