FIFA President Gianni Infantino is still recommending a 48-team World Cup in 2026 but now prefers to have 16 first-round groups of three teams each.
Infantino's suggestion was among four proposals which had been sent to FIFA Council members who will decide in January on the formats and number of teams for the 2026 World Cup, a source said.
Infantino had previously suggested a 48-team tournament but with a sudden-death preliminary round involving 32 teams.
The 16 winners would then go into a 32-team group stage along with 16 other teams who would receive a bye. This format remained on the table but was no longer Infantino's preferred option, the source said.
The other proposals were to keep the current 32-team format, or to have 40 teams with either eight groups of five or 10 groups of four.
If world football's governing body does not adopt the 16-group format, other options that will be considered include:
The number of teams competing at a World Cup last increased in 1998 when the tournament expanded from 24 to 32 countries.
Uefa's Euro 2016 tournament featured 24 nations, an increase from the 16-team format in place since 1996.