Australians working in Britain may not be able to stay there indefinitely if they are on a lower income, under new rules due to kick in this year.

The changes, which take effect from April, will mean non-European workers will have to earn at least £35,000 ($72,000) a year to be allowed to settle in the UK for longer than six years.

Australians at a pub in London.

The visa move, which was first flagged in 2012, will apply to those outside the European Economic Zone in a bid to "break the link" between working and staying permanently in Britain.

It follows a Cameron government push to reduce migration numbers, with estimates the numbers of non-European skilled workers settling in Britain each year would drop from 60,000 to 20,000 under the change.