FIFA, the game's world governing body, had said the Video Assistant Referee (VAR) system would be used at the finals if approved by IFAB, but its European counterpart UEFA has said it will not be deployed in next season's Champions League.
FIFA president Gianni Infantino said the final decision on using the system at the June 14-July 15 World Cup will be taken at a meeting of the FIFA Council in Bogota later in March.
"As of today, the VAR system is part of football," he told reporters. "We came to the conclusion that VAR is good for football and referees, it brings more fairness to the game. For these reasons we have decided to approve it."
Critics say VAR has led to confusion in competitions where it has been used, especially for spectators in stadiums who are often unaware that a decision is being reviewed.
The International Football Association Board (IFAB) statement described the move as an "historic step for greater fairness in football."
According to IFAB protocols, VAR should only be used in four key cases: goals, penalties, direct red cards and mistaken identity.
A trained referee with access to a video monitor, and in constant communication with the main match official, checks all such decisions.
If a "clear and obvious" mistake is spotted, the incident can be reviewed and changed. The referee, who has access to a pitchside monitor, can also initiate a review himself.
The implementation of the VAR system has been one of Infantino's main projects since he was elected in February 2016.
"I can guarantee that the referees that will be at the World Cup will be ready," he said on Saturday.
"Regarding the flow of the game, the intervention takes around one minute. I believe that VAR at the World Cup will certainly help us to have a fairer World Cup."
(Writing by Brian Homewood; Editing by Ken Ferris)
