Chinese military presence in the Solomon Islands would require Australia's defence force to recalibrate how it conducts operations, a senior army officer says.
It comes amid concerns about a proposed Sino-Solomons security pact that involves police, security forces and training.
Chief of Joint Operations Lieutenant General Greg Bilton says it would be an unusual circumstance to be co-operating with the Chinese in the Solomon Islands, with Canberra and Beijing both providing training to the same organisation.
"It does change the calculus if Chinese navy vessels are operating from the Solomon Islands," he told reporters on Thursday.
"They are in much closer proximity to the Australian mainland and that would change the way we would undertake day-to-day operations, particularly in the air and at sea."
Lt Gen Bilton said such a presence would result in changed patrolling patterns and maritime awareness activities.
But the Solomon Islands have pushed on despite the concerns, with Minister for Foreign Affairs and External Trade Jeremiah Manele saying the two nations had "initialled" elements of the bi-lateral security pact.
"The draft framework agreement will be cleaned up and await signatures of the two countries' foreign ministers," the Solomon Islands government said in a statement on Thursday.
The Pacific nation reiterated the pact is to respond to soft and hard domestic threats and it would continue its foreign policy epigraph: "Friends to all and enemies to none".
"The country will work with all partners in providing a safe and secure nation where all people are able to co-exist peacefully," the statement says.
AFP Commissioner Reece Kershaw said he had been aware there was going to be some form of training proposal from China but he had not personally seen the proposed memorandum of understanding for a security pact.
But Mr Kershaw said Australia wanted to remain the partner of choice for the Solomon Islands police.
"We've been there a long time ... (and) it is a little bit personal. We did lose an officer of ours," he told Senate estimate hearings.
"So we're not about to let other countries come in and try and change that whole framework. It works.
"Community crime has dropped there, the police force are more professional than ever before and we want to maintain that position of being the partner of choice in the region."
Micronesia President David Panuelo has also expressed "grave security concerns" at the agreement in a letter to Solomon Islands Prime Minister Manasseh Sogavare.
Mr Panuelo expressed gratitude for the help China had offered his country and reiterated the same foreign policy line as the Solomons, but noted the US and China were increasingly at odds.
"My fear is that we - the Pacific islands - would be at the epicenter of a future confrontation between these major powers," he wrote.
Mr Panuelo expressed concerns that a Chinese military presence would attract conflict and the Pacific islands would become collateral damage.
"It's not an impossible fear; it has happened before. Both the Federated States of Micronesia and Solomon Islands were the battlegrounds during World War II.
"As we can see from Russia's invasion of Ukraine, the bigger countries will choose violence if they think it serves their interests, and without regard necessarily to our interests, such as not to become collateral damage."
Finance Minister Simon Birmingham denied Australia had failed in its Pacific foreign policy despite a senior official at the Department of Prime Minister and Cabinet revealing he was unaware of any phone conversations between Prime Minister Scott Morrison and his Solomons counterpart.
"The government is very conscious of ensuring that we respect the sovereignty of every Pacific island nation," Senator Birmingham said.
Mr Morrison has said the Solomon Islands government has not raised any issues about the support provided by Australia.
