Ronaldo was sent off in Portugal's 2-0 qualifying defeat to Ireland after elbowing Dara O'Shea's back earlier this month.

The red card, which was upgraded from an initial yellow card after a video assistant referee (VAR) check, was Ronaldo's first in 226 international appearances for Portugal.

Ronaldo missed the subsequent 9-1 victory over Armenia as Portugal secured ist FIFA World Cup qualification in the final game.

Violent conduct usually carries a three-match ban, but Ronaldo has had the second and third matches suspended for a year, so he will not miss any games at the FIFA World Cup next year.

A FIFA statement read: "If Cristiano Ronaldo commits another infringement of a similar nature and gravity during the probationary period, the suspension set out in the disciplinary decision shall be deemed automatically revoked, and the remaining two matches must be served immediately."

Article 27 allows FIFA's judicial body "to fully or partially suspend the implementation of a disciplinary measure".

Beyond citing article 27, FIFA did not explain in its statement why the ban had been suspended.

Ronaldo, who scored five goals in qualifying, will play in his sixth and final FIFA World Cup in the United States, Canada and Mexico next year.

Portugal will find out who it will face in its group at the tournament in the draw on 6 December (AEDT).