UEFA warns that staging of international matches will be at risk if its protocols for the return of the Champions League and Europa League are not observed.
Both tournaments resume this week after a five-month delay because of the coronavirus pandemic.
The protocols were distributed to all 28 teams still in the two competitions.
Both competitions conclude with ‘final eight’ tournaments behind closed doors in Portugal and Germany.
The UEFA Champions League final will be held in Lisbon on 23 August, two days after the Europa League final takes place in Cologne.
“Uefa expects all parties to adhere to hygiene best practices both in the controlled match environments, as well as in their private day-to-day lives,” the protocols state.
“It is imperative that all precautions set out in this document, as well as the standard hygiene best practices, will be strictly adhered to by all members of these various groups.
“Non-respect of such social norms could have serious consequences for the staging of international matches.”
The return of European club competition will immediately be followed by the start of the Nations League international qualifiers at the beginning of September.
In addition, the 2020-21 European club season starts on 8 August, with Northern Irish side Linfield involved in the Champions League preliminary round.
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