Brisbane's Lord Mayor has resigned from the 2032 Olympic and Paralympic Games advisory body, claiming mismanagement.
Adrian Schrinner said the Intergovernmental Leaders' Forum was a "dysfunctional farce and a pointless talkfest" and the Queensland government was making the "real" decisions behind closed doors.
"The Games are a once-in-a-lifetime opportunity for Brisbane and Queensland," he said on Sunday.
"Unless the state government's approach changes, this opportunity will be squandered through mismanagement."
Mr Schrinner also withdrew his support for the state government's plan to demolish and rebuild the Brisbane Cricket Ground, commonly known as the Gabba
The $2.7 billion plan was released on Friday and would make the revamped stadium the centrepiece for the Olympics, with capacity boosted by about 10,000 to 50,000 for sporting events.
Mr Schrinner was critical of the plan, saying it would come at the cost of promised public transport developments and see Brisbane teams pushed out of the city.
He renewed his call for an independent Games co-ordination authority, claiming Premier Annastacia Palaszczuk's government was using the event as its "political plaything".
"The government has completely lost its way on the road to the Games," he said.
"This has put the promised legacy for our city, our region and our state in serious jeopardy."
Mr Schrinner said an independent authority should be in charge of the Gabba redevelopment.
Under the redevelopment plan, the Gabba will be out of action for four years, meaning AFL side the Brisbane Lions and Queensland Cricket will need to find makeshift home grounds until 2030.
The redevelopment will feature three new pedestrian bridges and improved public transport links as part of Queensland's biggest urban renewal since South Bank's Expo 88 redevelopment.
Federal Treasurer Jim Chalmers previously said southeast Queensland had a chance to become the nation's most dynamic economy with the Gabba rebuild and 2032 Games.