UEFA announced the 2020 European Championship will be played in 13 countries, with each host providing a single stadium.
UEFA will encourage smaller countries to join the project by choosing two stadiums holding as few as 30,000 spectators. Other stadiums must have at least 50,000 capacity.
UEFA President Michel Platini says Turkey is his favored choice to host the final and both semifinals.
However, Platini says a Turkish bid will be "out of the question" if Istanbul is chosen in September as the host of the 2020 Olympics.
The other 12 Euro 2020 hosts will hold three group-stage matches and one match in the knockout rounds.
Host cities will be chosen in September 2014.