Australia has, for the first time, activated its newly introduced “arrival control determination” powers, temporarily preventing nearly 6,800 Iranian nationals holding valid Visitor (subclass 600) visas from travelling to the country.The six-month order was signed by Home Affairs Minister Tony Burke on 25 March 2026, amid concerns that escalating unrest in Iran could leave visitors stranded in Australia, placing unforeseen pressure on the migration system.The move is enabled under Section 84B of the Migration Act 1958, legislation fast-tracked through Parliament earlier this month with bipartisan backing. The provision allows the government to temporarily halt arrivals for specific visa groups without revoking the visas themselves.Under the determination, affected travellers are barred from boarding flights unless granted an individual exemption. Airlines that fail to comply risk significant penalties. While the framework draws on pandemic-era border controls, it is now being applied on national interest and public order grounds rather than public health.Officials revealed during a Senate hearing that around 7,200 Iranian nationals currently hold temporary Australian visas, with the vast majority—approximately 6,800—remaining overseas on tourist visas.Mr Burke stated that exemptions would be considered in compassionate circumstances, particularly where close family ties exist, such as parents of Australian citizens. However, advocacy groups argue that the exemption process is stringent and places a heavy evidential burden on applicants.The restriction does not apply to Iranian nationals already within Australia, nor does it currently extend to student, work or humanitarian visa categories.The decision has prompted travel and business advisory firms to reassess risks. Companies have been urged to review travel plans involving dual Australian-Iranian nationals and reconsider transit routes through regional hubs such as Tehran, Doha and Dubai.Although corporate travel visas remain unaffected, experts warn the measure signals a tougher border stance that could be expanded if geopolitical tensions escalate.