"It's an essential, important and historic decision, based on the meeting of IFAB two weeks back".
A North American bid combining the United States, Canada, and Mexico is competing with Morocco for the right to host the first 48-team tournament in eight years' time.
"We also spoke about football, we're going to have our first World Cup in 2018 with [the] video assistant refereeing system", Infantino told a news conference.
Meanwhile, FIFA said it was lifting the three-decade ban on Iraq hosting global football with the cities of Arbil, Basra and Karbala given the go-ahead to stage official matches. From Twitter, FIFA council member Reinhard Grindel showed his support, explaining that clear communication is vital to a successful tournament.
The U-20 World Cup has featured players such Diego Maradona and Lionel Messi - who would go on to becomes legends of the game.
Infantino said no one on the FIFA Council was against the decision, and added: "We didn't take it lightly".
Jose Mourinho Scorches Frank De Boer Over Rashford Comments
Paul Pogba remains a doubt with a leg injury picked up in training last week. "In training is where I'm doing most of my learning".
The system that allows off-pitch referees to re-examine a decision or an incident referred to them by the match official has been used in Germany's Bundesliga and Italy's Serie A this season and trialled in some English FA and League Cup games.
"I was sceptical at the beginning but without trying things you can't know what they are worth".
The use of Video Assistant Referees (VAR) is one of the most polarizing issues in modern football. That's why we carried out trials in those 1,000 matches. These are facts and figures. "We need to leave one percent, we can not provide 100".
"It can not be possible that in 2018 everybody, in the stadium or at home, knows in a few seconds if the referee has made a mistake but not the referee himself - not because he doesn't want to know about it but because we forbid him to know".
A Fifa ruling in Colombia on Friday approved of the decision, after the International Football Association Board reached a unanimous decision to introduce the technology earlier this month.
"Nobody knows exactly how VAR will work".