Infantino said in October there was a 'positive feeling' about expansion and, on stage at the Dubai International Sports Conference on Wednesday, appeared to suggest consensus was growing.
BBC Sport reported the Swiss telling the conference that regional federations were 'overwhelmingly in favour' of the proposal.
FIFA, and Infantino, are now thought to prefer a competition with 16 groups of three, having initially considered a design that would see 16 teams eliminated after just one match, but expansion to 40 sides remains possible.
Italian newspaper Gazzetta dello Sport quoted Infantino as saying: 'I am still convinced to expand the participation in the World Cup more than 32 teams.
'We would still consider to increase the competition to 40 or 48 teams. A tournament to 48 teams would have the same period of the current one, and federations are clearly in favour of a World Cup with more teams.'
While Infantino appears confident his plans will find favour at the FIFA council, there has already been discontent from other notable areas.
The European Club Association, an amalgamation of 220 top teams in the continent, outlined its concerns earlier this month.
Karl-Heinz Rummenigge, chairman of both the ECA and Bayern Munich, said: 'In the interest of the fans and the players, we urge FIFA not to increase the number of World Cup participants.
'Politics and commerce should not be the exclusive priority in football.'
The ECA is understood to be concerned at the growing demands on top players. A 16 group solution would increase the number of players involved during a World Cup summer but not necessarily the maximum number of games for any side or individual.
Infantino also used his stage in Dubai to give a thumbs up to video assisted refereeing, as trialled in the recent Club World Cup and mooted for use at the 2018 World Cup in Russia.
'The tests have been very positive and they are going in the right direction,' said Infantino.
