UEFA has confirmed clubs will be allowed to make up to five substitutions per match in the Champions League and Europa League throughout 2020-21.

The Executive Committee of European football's governing body met on Thursday to rule on a variety of matters for 2020 and 2021.

Arguably the biggest decision made was to extend the rule alteration relating to substitutions, which allowed teams to make up to five in-game changes after the coronavirus crisis forced top-flight football to a halt earlier this year.

The International Football Association Board (IFAB), rule-makers for the sport, initially implemented the change in May and extended it two months later for club competitions set to be completed by July 31, 2021 and international tournaments scheduled in July/August 2021.

While some domestic competitions, such as England's Premier League, have opted to revert to three substitutions allowed per team in each match, UEFA believes it is necessary to permit five "in order to alleviate the burden on players caused by the condensed international match calendars 2020-21 due to the COVID-19 pandemic".

The five substitutes rule will be extended to Euro 2021 qualifying playoffs, Women's EURO qualifiers, the Nations League group phase and the Women's Champions League for the rest of the season.

Among the other decisions communicated on Thursday, UEFA – having reached an agreement with the European Club Association and the European Leagues – will stretch the March and September international match windows in 2021 to allow for three fixtures instead of two.

UEFA says this will allow it to "recover the dates lost due to the cancellation of the March 2020 window and the postponement of Euro 2020".

It was also confirmed that the format of the UEFA Youth League has been temporarily altered – rather than beginning with a group phase, the competition will start at the round of 64 in March as a straight knockout competition.