A dramatic drop in the number of international students enrolling in WA could be costing the state hundreds of millions of dollars, according to the opposition.

New figures released by the federal Department of Education revealed 8.2 per cent fewer overseas students commencing studies this year in WA, the only state to record a decline.

The number of new international students climbed by 7.7 per cent in Victoria, 7 per cent in Queensland and 6.3 per cent in New South Wales.

A row erupted in parliament on Thursday after the state government promised to introduce a pathway for high-achieving foreign graduates to migrate.