WA Premier Colin Barnett explains why he's not joining the latest push for an Australian republic referendum

Every Australian state and territory leader has signed a declaration supporting the end of the constitutional monarchy, except for WA Premier Colin Barnett - who says it’s not the right time.

Mr Barnett said he supported a republic and expected it to happen in his lifetime, but thought it had not been long enough since the last public vote on the matter.

“While I believe and hope that Australia will choose to become a republic in my lifetime, I do not think that the time is right, or that sufficient time has passed since the referendum, to be again prosecuting the argument for constitutional change,” he said in a statement.

He said he had accepted the outcome of that referendum as a “democratic expression of the public will”.

Head of the Australian Republican Movement Peter FitzSimons said he was “bemused” by Mr Barnett’s response but that it didn’t matter because the leaders were still united in support for a republic at some time.

He said there was no better time than Australia Day for “national reflection” and urged Prime Minister Malcolm Turnbull to "seize this moment" rather than waiting for the Queen to die.

“Have the Queen come when she’s young enough and instead of bowing and curtseying the nation rises as one in a standing ovation and says ‘thank you your majesty we will take it from here’,” Fitzsimons said.

The declaration simply read: “We, the undersigned Premiers and Chief Ministers of Australia, believe that Australia should have an Australian as our head of state.”