By Andrew Greene, ABC Defence Correspondent
Almost 200 Australian sailors are bracing for confrontation with Iranian vessels as their warship sets sail today for a maritime security mission in one of the world's most treacherous waterways.
HMAS Toowoomba will be formally farewelled from the Stirling naval base south of Perth on Monday, ahead of a six-month deployment to the increasingly tense Strait of Hormuz.
There the ANZAC-class frigate will join an American-led coalition protecting oil supplies leaving the crucial trading passage, against a backdrop of escalating military tensions between the United States and Iran
The ABC has been told the warship could be diverted elsewhere in the Middle East if the security situation deteriorates.
Australian Defence Minister Linda Reynolds said Toowoomba and its 190 sailors would support Australia's safe and open access to the region, and reaffirm the country's commitment to freedom of navigation.
"This highly capable vessel will focus on promoting maritime security, stability and prosperity in the Middle East by supporting counter-terrorism, preventing piracy, and freedom of navigation," she said.
Last year, Prime Minister Scott Morrison announced Australia would deploy a warship, surveillance aircraft and Defence Force personnel to the Persian Gulf to join international efforts to combat Tehran's actions in the Strait of Hormuz.
The deployment is part of Operation Manitou, the Australian Defence Force's contribution to promote maritime security and stability in the Middle East.
HMAS Toowoomba is the 68th rotation of a Royal Australian Navy warship to the region since 1990.
Navy Chief Vice Admiral Michael Noonan said HMAS Toowoomba was ready for its Persian Gulf mission following 12 months of preparation.
"Commander Mitchell Livingstone and his crew have worked tirelessly to prepare for this deployment, and will form an integral part of the multi-national Combined Maritime Force and International Maritime Security Construct," Noonan said.
"We ask a lot of the men and women of Toowoomba who leave their families and friends for this deployment, but we also ask as much from those they leave behind."
In 2018, Noonan suggested Australia's 30 years of continuous maritime operations in the Middle East could soon wind down as concerns grew over China's rapid rise closer to home.
HMAS Toowoomba is scheduled to arrive in the Middle East within a fortnight, before returning to Australia in July.