CHICAGO, March 15 (Xinhua) -- Chicago has dropped out as a possible hosting site in United States' bid to co-host the 2026 FIFA World Cup, local media Chicago Tribune reported Thursday.

Soldier Field stadium in downtown Chicago was one of 32 potential venues on a list released last year by the joint bid committee that's vying to bring the world' s biggest sporting event to the U.S., Canada and Mexico.

But Matt McGrath, a spokesman for Mayor Rahm Emanuel said in a statement released Wednesday that FIFA was unable to provide "certainty" that Chicago taxpayers would not be affected if selected as a host city.

"The uncertainty for taxpayers, coupled with FIFA's inflexibility and unwillingness to negotiate, were clear indications that further pursuit of the bid wasn't in Chicago's best interests," McGrath said in the statement.

FIFA insists that contracts with host cities contain a provision that be governed under Swiss law and give FIFA the ability to modify agreements at any time.

Vancouver in Canada's British Columbia also pulled out for the bid as officials said provisions add "unknown costs and unknown risks to the taxpayers."

Morocco is the other bidder besides the joint U.S., Canada and Mexico. The FIFA Congress votes to decide on the winner on June 13 in Moscow.