There are concerns changes to skilled migration rules could further tarnish Australia's reputation abroad with the revamp to leave thousands of foreign students in limbo.

Under the changes, the list of jobs used to select migrants is to be streamlined and reviewed annually, while potential new Australians will need to have better English-language skills.

As a result, about 20,000 people will have their migration applications cancelled and their fees refunded at a cost of about $14 million.

The changes also leave thousands of overseas students facing uncertainty with many to lose the chance to apply for permanent residency because the job for which they are studying will no longer be on the skilled list.

Students affected by the changes will be able to apply for a temporary skilled graduate visa to stay in Australia for 18 months while they gain work experience or seek sponsorship from an employer.