Two Iranian warships have been tracked passing through the South Pacific on a global deployment aimed at demonstrating the Islamic republic's growing military power and maritime reach.
During November an Iranian frigate, accompanied by a converted oil tanker, docked in Jakarta before heading to the Pacific, but at no stage did either vessel enter Australia's exclusive economic zone (EEZ).
A Defence spokesperson confirmed the Iranian vessels had been monitored by Australia while operating in this region.
"As part of Australia's broader whole-of-government maritime border protection efforts, Defence routinely monitors maritime traffic in the vicinity of our exclusive economic zone and maritime approaches," the spokesperson said.
"Defence has been aware of two Iranian warships operating in the Indo-Pacific for some time."
In February last year, two Chinese warships that had also sailed past Indonesia entered Australia's EEZ in the Arafura Sea before heading out towards the Pacific Ocean via the Torres Strait.
Unlike the Chinese vessels, which aimed a high-powered laser at an RAAF surveillance plane, the Iranian warships headed towards the Philippine Sea after leaving Indonesia rather than continue eastward through Australian waters.
"At no time has either Iranian vessel entered Australia's exclusive economic zone, nor have they transited through the Torres Strait and there has been no communication with them," a Defence spokesperson confirmed.
On Christmas Day, France's Pacific Command revealed it had made contact with the Iranian vessels after they declared their intention to pass just below the remote Marquesas Islands.
A Falcon 200 surveillance aircraft monitored the IRIS Dena and IRIS Makran as they approached French Polynesia's EEZ.
Maritime analysts told the ABC there was no evidence the Iranian warships made any port visits while in the Pacific, but they believe the flotilla also passed close to the Solomon Islands.
Circumnavigating the globe to exhibit Tehran's military power
The forward base ship IRIS Makran and frigate IRIS Dena form the Iranian Navy's 86th Flotilla, which departed the Islamic republic at the end of September for an historic worldwide deployment.
Shortly after their departure, Iran's navy chief declared the warships would circumnavigate the globe during their mission to "show the authority of the dear people of Iran to the whole world".
Speaking to state television in December, Rear Admiral Shahram Irani said it was important for Iran to demonstrate its growing naval capacity.
"What is important in the matter of maritime presence is authority … presence in the seas means power and authority," the navy chief explained.
"The first message that a frigate or submarine sends out is that the country that builds them has acquired the required knowledge to dominate the sea."
The navy chief also revealed that sailing to Australia was one of his lifelong ambitions.
"I myself was interested in experiencing new environments since my childhood, and I had a special interest in the sea," the rear admiral told Iran's state-owned Press TV.
"My dream was to sail across the Indian Ocean some day and reach Australia."
Singapore-based geopolitical analyst Patrick Dupont said the presence of Iranian warships in Australia's region was not surprising given recent statements from Tehran, and he expected further future visits.
"It's quite well known that Iran is an isolated underdog certainly in the Middle East, and internationally – they need friends, basically," Mr Dupont told the ABC.
The former Australian Army analyst predicted Iran's "routine acts of naval diplomacy" would continue and potentially become an annual operation.
"Iran's navy is certainly going to continue to develop. I don't think they're going to cut military spending, and so of course they're going to test their ships," he said.
"They want to know how far they can sail, but in reality, their focus is always going to be in the Persian Gulf – that is going to be their main effort in terms of strategic planning for their navy."