Jose Mourinho believes an expanded World Cup tournament would develop the sport in areas lacking strong soccer foundations without proving to be a burden for both clubs or players in major leagues.
FIFA President Gianni Infantino wants to increase the quadrennial tournament to 48 nations from 2026 but Europe's leading clubs remain opposed to plans to expand the World Cup beyond its current allocation of 32 teams.
The FIFA Council is expected to reach a decision this month on whether to add more teams to the tournament format.
"I'm totally in favour. As a club manager, if the expansion meant more games, less holidays and less pre-season for players, I would say no," the Manchester United manager told FIFA's website (www.fifa.com) when asked about expansion plans.
"It's important for critics to analyse and understand that expansion doesn't mean more matches. Players are protected and clubs are protected in this way. Teams with less potential and experience will probably play two matches and go home.
"But they would do so having improved and gained experience on the pitch, which would be added to the economic rewards of appearing at the finals -- including further investment in their footballing infrastructure."
Opponents of the expansion plans fear that a format change would lead to a drop in the quality on display at the finals but Mourinho felt that notion was unrealistic.
"The expansion means that the World Cup will be even more of an incredible social event. More countries, more investment in different countries in infrastructure, in youth football," he added.
"Football is developed in the clubs, so we can't expect football to explode in terms of quality at a World Cup."
Mourinho also said that scepticism should not stand in the way of evolution after Real Madrid manager Zinedine Zidane and midfielder Luka Modric were critical of the video technology that was tested at last month's Club World Cup.
"We all need it (video technology). Professionals can't lose or win matches and titles because of a refusal of this evolution," the 53-year-old added.
"Also, referees especially need and deserve protection. They need the technology to help them, protect them and to support them."