From The Australian:

Tony Abbott will announce in Perth as early as today that the ­federal government has agreed to hand Western Australia a one-off revenue bonanza of at least $600 million to compensate for the state’s plummeting GST share.

In a move designed to placate Premier Colin Barnett — who last month threatened to “disengage” from the rest of the nation — the Prime Minister is set to boost funding for joint commonwealth-state projects, including the $1.5 billion Perth Freight Link. The move could help shore up support for the Coalition in Western Australia, where Newspoll support for the Abbott government has crashed in recent months.

It will also reduce the state’s forecast budget deficit for 2015-16, to be announced next week.