Australia today tightened its immigration rules rejecting over 20,000 migrant applicants from foreign students, including Indians, seeking permanent residency through hairdressing, cookery and other courses.

The fresh system has set a new list of occupations in demand and has favoured skilled workers including nurses, general medical practitioners, mechanical engineers and teachers instead of groups such as cooks and hairdressers.

The tough immigration rules are aimed at curbing the activities of unscrupulous agents who promise students taking up courses here with automatic entitlement to permanent residency. "It does not and it will not," Immigration Minister Chris Evans said on such claims.

"The current points test puts an overseas student with a short-term vocational qualification gained in Australia ahead of a Harvard-educated environmental scientist," Evans said in a statement.

Evans said the reforms, which follow a sudden rise in Australia's Indian population and a spate of attacks on students from the country, would give priority to migrants with higher skills.

"We had tens of thousands of students studying cookery and accounting and hairdressing because that was on the list, those subjects were on the list and that got them through to permanent residency," he told ABC radio.

Australia has over one lakh Indian students, about 19 per cent of total foreign enrollments.