UEFA have announced a change to the format of their Nations League international competition among a raft of decisions at their Executive Committee meeting in Ljubljana, Slovenia.
The new structure sees 16 teams in Leagues A, B and C, with seven in League D, with changes for the 2020-2021 season.
Nations are allocated to the various divisions based on their rankings in the 2018-2019 competition, meaning that Germany, Iceland, Croatia and Poland remain in the top tier and are reprieved from relegation after finishing bottom of their divisions.
UEFA say the change was made after consulting the 55 national associations and "reflects upon their desire to further minimise the number of friendly matches".
They also say the change "enhances sporting fairness" as it means the final group games in Leagues A, B and C can all kick-off at the same time with all teams involved, which was not possible with the previous three-team pools.
The finals tournament, involving the four League A group winners, is unchanged.
UEFA also announced that Saint Petersburg, Munich and London will host the Champions League finals between 2021 and 2023.
The Russian city will host in 2021 and the final will be in Germany in 2022, before being played at Wembley in 2023.
The 2021 Europa League final will be held at the Ramón Sánchez Pizjuán in Sevilla, with the 2021 Super Cup final taking place in Belfast, Northern Ireland.
The host nations for the 2021 and 2022 UEFA men's and women's international Under-17 and Under-19 Championships were also announced.
Cyprus will host the men's under-17s in 2021 with Israel holding the competition in 2022, while the men's under-19s will be played in Romania in 2021 and in Slovakia the following year.
Faroe Islands will host a UEFA competition for the first time with the 2021 women's under-17s, which will go to Bosnia and Herzegovina in 2022.
The women's under-19s will be played in Belarus in 2021 and the Czech Republic the following year.
UEFA also announced a wider roll-out of Video Assistant Referees (VAR) in their club and international competitions.
VAR will be implemented for the knockout stages of this year's Europa League and the Women's Champions League final, as well as at the 2021 Women's European Championships.