Australia opener Usman Khawaja has again accused the International Cricket Council (ICC) of double standards after being refused permission to display a dove of peace on his bat during the Boxing Day Test.

The Pakistan-born Khawaja, who has been keen to show his support for the people of Gaza during the ongoing conflict in the enclave, was reprimanded for wearing a black armband in the first test against Pakistan in Perth earlier this month.

He had originally intended to show his support by writing the messages "Freedom is a human right" and "All lives are equal" on his boots in the colours of the Palestinian flag but that gesture also fell foul of ICC regulations.

Khawaja had worked with Cricket Australia on a new way to show his support by having the dove on his bat accompanied by the message "01: UDHR" in a reference to the first article of the Universal Declaration of Human Rights.

According to The Australian newspaper, the ICC also refused to allow him to display the message.

There was no immediate reply to a request for comment on the matter from the ICC.

In a video on Instagram late on the eve of the second test against Pakistan at the Melbourne Cricket Ground (MCG), Khawaja posted pictures of other international players with religious symbols and messages on their bats.

"Merry Christmas everybody, sometimes you just gotta laugh ... #inconsistent #doublestandards," he wrote underneath.

The ICC Code of Conduct forbids players wearing, displaying or conveying messages through arm bands or other items on clothing or equipment without prior approval, especially for "political, religious or racial" causes.

Israel's ongoing assault on Gaza in response to the deadly Oct. 7 cross-border attacks by Hamas has killed at least 20,700 Palestinians, according to the Gaza health ministry.

Australia captain Pat Cummins said on Monday that the team were sympathetic to Khawaja's desire to show his support to the people of Gaza.

"I don't know the ins and outs of the application, but I think it is pretty vanilla, a dove," he told reporters.

"We really support Uzzy, I think he's standing up for what he believes and I think he's doing it really respectfully," he said.

"He can hold his head high the way he's gone about it, but there's rules in place, so I believe the ICC have said they're not going to approve that. They make up the rules and you've got to accept it."