FIFA president Gianni Infantino confirmed Wednesday that video assistant referees will be used at next year's World Cup in Russia for the first time.
"We will use video refereeing at the 2018 World Cup because we've had nothing but positive results so far," he said at a congress of the South American Football Confederation (CONMEBOL) in Santiago, Chile.
"In 2017, when everyone in the stadium or at home can see within seconds if the referee made a mistake, we can't have a situation where the only one who can't see it is the referee."
Video assistance was introduced to support referees with "game-changing" decisions for the first time in a FIFA competition at the Club World Cup in Japan in December.
The four areas covered by the video replay official were goals, penalties, red cards and cases of mistaken identity.
Infantino had already said he wanted video refereeing for the next World Cup, but that "little hiccups" would have to be worked out first.
That included slow decision-making by video assistant referees, he said at a meeting of the International Football Association Board in March.
But that is only a matter of training, he said at the time.
"The referees... will be able to take decisions much faster when they use it more often," he said.
CONMEBOL said Wednesday it was considering ways of boosting attendance at the 2019 Copa America, South America's top international tournament, which will take place that year in Brazil.
Proposals include raising the number of competing countries to 16 from the usual number of 12, CONMEBOL's vice-president Arturo Salah said.
It has also been suggested that European countries be invited to take part.
"The Copa America with European teams would be like a World Cup. That is a discussion for another time," Infantino said.