Video Assistant Referees (VAR) technology will be used in the knockout stages of this season's Champions League and Europa League competitions.
European football's governing body confirmed the move following the meeting of its executive committee in Dublin.
VAR will also be used at next summer's Nations League Finals - which will feature England as well as Portugal, Holland and Switzerland.
Having been trialled at the World Cup in Russia, as well as certain FA Cup and League Cup fixtures in English football, the technology will also be used in the Premier League from next season after clubs agreed the introduction in principle at a meeting last month.
"The obvious change is we have had fewer important mistakes," former referee Howard Webb told BBC Sport. "The ethos is to benefit the game without interfering with how it is played.
"In MLS, we have seen almost 100 errors rectified by the use of video review and those are errors that would have been significant because they relate to direct red cards, goals and penalty kicks primarily."
Additional reporting by the Press Association.
