WA constitution changes unlikely to pass

Legislation to recognise Aboriginal people as the first people of Western Australia is unlikely to pass after ministers admitted the government will vote against it.

Opposition leader Mark McGowan said health minister Kim Hames and planning minister John Day had told a Labor MP that the government wouldn't support the Labor-proposed bill, which was scheduled to be voted on in parliament on Wednesday.

Mr McGowan claims Premier Colin Barnett doesn't want to support the bill, which was introduced to parliament in June, because it's not his idea.

Mr McGowan says WA is a sovereign state and doesn't have to wait for the Commonwealth to recognise Aboriginal people in the constitution.

"It's not a big ask, every other state has done it," he told reporters.