According to Infantino, the proposal could take effect from the 2026 World Cup.
"The idea is that 16 teams would qualify directly to the group stage and the other 32 would play in a preliminary phase, in the country where the World Cup is being played," Infantino told reporters at an event in Bogota, Colombia on Tuesday.
"They would play for the remaining 16 places. It means we continue with a normal World Cup for 32 teams, but 48 teams go to the party."
One of Infantino's proposals while coming out for election was to increase the number of teams competing in FIFA World Cups to 40 after Qatar 2022.
"These are ideas to find the best solution. We will debate them this month and we will decide everything by 2017," Infantino continued.
"They are ideas which we put forward to see which one is the best. FIFA's idea is to develop football in the whole world, and the World Cup is the biggest event there is," he said. "It's more than a competition, it's a social event."