A 48-team World Cup has the backing of global football federations, according to FIFA president Gianni Infantino.
When running for election to the role, Infantino's manifesto included a proposal to increase the number of teams in the finals from 32 to 40.
And in October, Infantino hinted it could be expanded even further to include 48 countries - a vision he now believes can be realised, as it has the necessary support.
"I am still convinced to expand the participation in the World Cup to more than 32 teams," he said at the International Sports Conference in Dubai.
"We would still consider to increase the competition to 40 or 48 teams. A tournament of 48 teams would have the same period of the current one, and federations are all clearly in favour of a World Cup with more teams."
Any revision to the existing format would not be likely to be implemented before 2026, but a decision on the matter will be taken in January.
UEFA made a similar move in increasing the European Championship from 16 teams to 24 ahead of Euro 2016.
Earlier this month, the European Club Association (ECA) wrote to FIFA imploring global football's governing body not to proceed with plans to expand the tournament.
ECA chairman Karl-Heinz Rummenigge said: "In the interest of the fans and the players, we urge FIFA not to increase the number of World Cup participants."