Foul-mouthed Cheika escapes punishment
His outburst came during the Wallabies' crushing loss to England last weekend.
Cheika – who has a long history of disciplinary missteps – was infuriated by several decisions that went against Australia at Twickenham last Saturday.
When a Michael Hooper try was disallowed in the first half, he appeared to mouth an expletive in reference to the ruling made by referee Ben O'Keeffe.
When asked during a broadcast interview if he had actually mouthed an expletive and called New Zealand's O'Keeffe a "cheat", Cheika ended the interview.
He was also caught on camera sarcastically applauding decisions that went against Australia in the 30-6 defeat and twice walked down the steps from the coaches' box to the touchline to remonstrate with officials.
International disciplinary officials had probed the incidents for several days and on Thursday announced a warning was sufficient censure for Cheika.
"Cheika and the Australian Rugby Union cooperated with the investigation, which has now been completed," a statement read.
"In light of Cheika's explanations of his conduct, his clear understanding of the need to protect and promote the interests of the sport, and his open apology for any offence caused, the Disciplinary Officer for the Autumn Internationals (in consultation with World Rugby) has decided not to pursue any disciplinary proceedings against Cheika.
"The Disciplinary Officer has, however, urged Cheika to be aware of the risks during matches when he knows he will be being filmed and potentially broadcast, and where possible to moderate his conduct and language accordingly. Cheika has accepted the position."
Cheika called into question rugby union's replay procedure after several decisions went against his side during a match where the scale of Australia's defeat was compounded by England running in three late tries through Jonathan Joseph, Jonny May and Danny Care.
With England just 3-0 ahead, Australia was denied a 27th-minute try on review after Wallaby captain Hooper was ruled to have been in front of the kicker.
Australia was still in the game at 13-6 behind when what appeared to a try by wing Marika Koroibete was eventually disallowed for a block by replacement hooker Stephen Moore.
To make matters worse for the Wallabies, the 54th-minute try that England's Elliot Daly scored to give the hosts a decisive 11-3 lead was awarded after numerous replays failed to determine if a kick by scrum-half Ben Youngs, that the Wasps wing hacked on and then regathered, had first gone into touch.
There was a lengthy delay in each case as O'Keeffe consulted with Irish TV match official Simon McDowell.
Australia concludes their European tour against Scotland at Murrayfield on Saturday.