In the message, Mr Pezzullo said Australia must strive for peace, but not at the cost of its liberty.

"In a world of perpetual tension and dread, the drums of war beat - sometimes faintly and distantly, and at other times more loudly and ever closer," he told staff.

The development comes as Australia's relationship with China grows increasingly fractious, with Defence Minister Peter Dutton expressing concerns about Beijing's stance on Taiwan.

But Mr Pezzullo's speech is being seen as unhelpful in some quarters.

"Look, I'd just urge the Commonwealth and people in this position, elected and otherwise, to tone it down," the WA Labor Premier told reporters in Perth.

"Tone it down. What good does that do saying things like that? It's totally unnecessary.

"It gets a headline. No doubt probably secures you some coverage around the world. And there may be elements in the community who cheer, but it's in no one's - no one's - interest, that sort of language. Diplomacy should be conducted diplomatically by people in elected office and also by those who are public servants. So I would suggest to them they don't say things like that anymore."

Labor's foreign affairs spokeswoman, Senator Penny Wong, said the federal government needed to explain how Mr Pezzullo's words were consistent with government policy.

"I think words matter and this is not the sort of language that we generally use when we are trying to be sober and cautious," the senator told reporters in Adelaide.

"I would make the point they appear to be inconsistent with Mr Dutton himself, who said on Insiders: 'We are in peace time and we want to stay in peace time.' So his language is a little more measured."

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The Home Affairs secretary also appeared to strive for peace at one point in the staff message.

"Today, as free nations again hear the beating drums and watch worryingly the militarisation of issues that we had, until recent years, thought unlikely to be catalysts for war," Mr Pezzullo said, "let us continue to search unceasingly for the chance for peace while bracing again, yet again, for the curse of war."

Home Affairs Minister Karen Andrews on Tuesday confirmed she had read Mr Pezzullo's "very strong" speech in advance, and it was in line with government thinking.

"The overarching message from government is that we need to be alert but not alarmed," Ms Andrews told Nine on Tuesday.

"We're obviously very conscious as a government of what is happening in the Pacific region, in particular, and we will always put Australia first, second and third."

Nationals senator Matt Canavan said there was no doubt the drums of war were beating.

"It's not clear exactly what that might mean for us but that may be a risk that a wider conflict does occur, and we should absolutely be prepared for that," he told Sky News.

"I welcome Mike Pezzullo speaking frankly from his obviously well-informed position because I do think the Australian people need a wake-up call.

"We must be ready for the worst outcome."

Mr Pezzullo is widely tipped to become the next secretary of the Department of Defence.

His Anzac Day message also invoked the words of two US generals and reflected on Australia's ANZUS alliance with the United States.