Australia head coach Dave Rennie has apologised for calling the match officials "horrendous" after their defeat to Wales.

Rennie was critical of Kurtley Beale's yellow card for a deliberate knock-on, saying Nick Tompkins had done the same in the build-up for his try.

Rennie had expected an apology, but was instead issued with a written warning.

World Rugby said it "condemns any public criticism" of their match officials who they described as the "backbone of the sport" and without who "there is no game".

"More importantly, the values that are at the heart of the sport must be upheld," the governing body added.

Rennie's furious comments came in the post-match interview.

"I thought some of the decision-making by the officials tonight was horrendous and played a big part in the result," he said after the game.

"Kurtley Beale got sin-binned for slapping the ball down, they do the same thing and it clearly goes forward and they get seven points out of us.

"I'm obviously really disappointed with the result. We'll end up getting an apology next week, but it won't help the result."

Rugby Australia accepted the formal warning and issued the apology on behalf of Rennie.

It said: "Dave Rennie wishes to apologise to the match officials and to World Rugby for the choice of language used in post-match media commitments following the Wallabies Test match against Wales in Cardiff.

"The choice of language and its timing did not meet the standards required from a coach or official in upholding Rugby's core values of discipline, integrity and respect."

The apology comes the day after South Africa director of rugby Rassie Erasmus withdrew his appeal against his World Rugby suspension, after his hour-long rant about officials in the first British and Irish Lions Test.