UEFA's 54 member countries have voted to create a Nations League competition to start in September 2018.
The competition will replace most continental international friendlies and feed into qualifying playoffs for the 2020 European Championship.
It could later be incorporated into European qualifying for the 2022 World Cup.
"This is a very important decision for the future of football at the level of national teams,'' UEFA President Michel Platini said after the vote at European football's annual congress.
Platini had pledged to raise the status and commercial value of international football. It has struggled against competition from popular and lucrative European domestic leagues and UEFA's own Champions League.
UEFA acknowledged that 'friendly internationals are not providing adequate sporting competition'.
The Nations League tournament format is yet to be finalised, although it foresees 54 teams ranked in four divisions playing September-November 2018.
The 12 highest-ranked teams would play in four three-team groups in Division A. Those group winners would advance to a finals tournament in June 2019.
All 54 teams would still play in traditional Euro 2020 qualifying groups, which would be played March-November 2019.
The Euro 2020 playoffs would then be scheduled in March 2020. That lineup would be decided by Nations League results of teams which did not qualify directly in the top-two qualifying group positions.
Euro 2020 is being played across Europe in 13 different host cities which will be picked in September.
UEFA will likely try to include the subsequent Nations League in the European qualifying program for the 2022 World Cup in Qatar.