The Defence Minister, Phil Goff, says altering rules for the Regional Assistance Mission to Solomon Islands could put its future in doubt.
The Solomon Islands prime minister, Manasseh Sogavare, wants to review the law which governs the Australian-led mission.
The Facilitation of International Assistance Act gives immunity to RAMSI personnel, but the Solomon Islands' Attorney General, Julian Moti, wants that removed.
Mr Goff says it would be impossible for the mission to continue in those circumstances.
He says RAMSI is in Solomon Islands by invitation, and the vast majority of people support its work.