FIFA president pushed for the expansion for the 2026 tournament onwards
FIFA president Gianni Infantino says football's world governing body will encourage co-hosting of the World Cup when it is expanded to 48 teams.
The 2026 tournament will see an extra 16 countries qualify for the finals.
The format will see the 48 teams split into 16 groups of three teams with the top two advancing to the first knockout round.
Infantino says FIFA and World Cup organisers will need to be realistic about the demands of holding a bigger competition, with the potential for more than two geographically proximate nations coming together to stage the tournament.
"We will encourage co-hosting for the World Cup because we need FIFA to show we are reasonable and we have to think about sustainability long-term," said Infantino, who proposed the expansion to a 48 team World Cup.
"Maybe bring together two, three, four countries who can jointly present a project with three, four, five stadiums each. We will certainly encourage it. Ideally the countries will be close to each other."
Only once has the World Cup been co-hosted by different nations. That occurred in 2002 when South Korea and Japan staged the tournament together - the last World Cup Ireland qualified for.
Korea hosted the opening game between France and Senegal in the capital Seoul with the Japanese city of Yokohama hosting the final between eventual winners Brazil and Germany.
The European Championships hosted by UEFA have been co-hosted more than once. Euro 2000 was co-hosted by Netherlands and Belgium. Eight years later, Euro 2008 was hosted by central European neighbours Austria and Switzerland.
Four years later, Ukraine and Poland hosted Euro 2012 together, with Ireland's Group C fixtures based in Poland.
The next tournament, Euro 2020, will be held across 13 European cities in the first European Championships to break away from a single host or two co-hosts.
Dublin's Aviva Stadium is one of the venues that will definitely host fixtures. Other venues include London's Wembley Stadium, Bilbao's San Mames, the Amsterdam Arena, Munich's Allianz Arena and Roma's Stadio Olimpio.
Meanwhile, Infantino says he is unconcerned by the threat of violence at next year's World Cup in Russia.
Hooliganism marred Euro 2016, with fans from the nation largely blamed.
A BBC documentary featuring Russian hooligans threatening violence at next year's World Cup has been broadcast.
Infantino told AFP: "I am not concerned about trouble in 2018, I have full confidence in the Russian authorities."