Australia on Thursday extended tough refugee policies to any asylum-seeker who lands on its mainland, allowing them to be banished to remote Nauru or Papua New Guinea for detention.
Until now, the government only had powers to send boatpeople for indefinite detention in the Pacific when they reached its remote offshore territories such as Christmas Island.
The change, which was passed in parliament Thursday, strips away any advantage asylum-seekers get from reaching the mainland.
"It will ensure asylum-seekers who unlawfully arrive anywhere in Australia by boat without a visa will be subject to the same regional processing arrangements as asylum-seekers who arrive at an excised offshore place," said Immigration Minister Brendan O'Connor.
Most boats land at or are intercepted near the remote Australian territories of Christmas Island, close to Indonesia's Java, or the Cocos Islands in the Indian Ocean.
Both are considered to be "excised" from Australia for immigration purposes, meaning they are subject to special laws allowing for refugees who land there to be processed in regional centres in the Pacific.
To avoid detention boatpeople have increasingly been aiming for the mainland. One packed with 66 asylum-seekers managed to evade detection and reach Geraldton in Western Australia in April.
On Tuesday a boat carrying 42 people was intercepted near Darwin.
Australia's Human Rights Commission condemned the legislation's passage, saying it undermined the nation's obligations under the refugee convention.
"By targeting unauthorised maritime arrivals, the legislation discriminates against vulnerable people and penalises them because of the way they arrive in Australia," said Commission President Gillian Triggs.
Triggs said the move deepened concerns about the plight of those held in remote Pacific camps, where conditions have been described as harsh by the United Nations, and detention "arbitrary".
Australia is struggling with a steady influx of boats from Indonesia and Sri Lanka, with arrivals topping a record 16,000 last year.
The government announced a crackdown on Australia's refugee determination process this week, targeting fewer visas in a bid to up the deterrent stakes.
Though refugees come in relatively small numbers by global standards, the issue is a political flashpoint in Australia and is likely to be a key issue in national elections in September.
Several of the often rickety, overcrowded fishing vessels have sunk in recent years, killing hundreds of people and underscoring the perils of the journey.