Ukraine's ambassador to Australia has urged tennis officials to ban Novak Djokovic's father from the Australian Open after he was filmed posing with fans brandishing Russian flags. 

"He should be stripped of his accreditation. It's up to Novak and his team to address this and fix it," ambassador Vasyl Myroshnychenko told the AFP news agency on Friday.

Myroshnychenko also called on Djokovic, who is preparing to face Tommy Paul in the semi-finals of the tournament, to personally apologise and to clarify his stance on the Russian invasion. 

"It's important for Novak to address this situation," he said.

"He should apologise for what has happened and condemn the Russian invasion of Ukraine." 

'Bold political statement'

A video posted to a pro-Russian Australian YouTube account on Thursday showed Djokovic's father Srdjan posing with a man holding a Russian flag with Vladimir Putin's face on it. 

The video was captioned: "Novak Djokovic's father makes a bold political statement."

Serbian tennis reporters confirmed it was Djokovic's father and the Melbourne Age newspaper reported he said in Serbian: "Long live Russia."

Another man was photographed by AFP inside the stadium during Djokovic's match with a T-shirt bearing the pro-war "Z" symbol.

Tournament organiser Tennis Australia said on Thursday it would continue to work with security to enforce entry rules, without directly addressing the incident with Djokovic's father.

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