Federal Labor has pledged an extra $400 million to the fund designed to make up for Western Australia's GST revenue shortfall.
Opposition Leader Bill Shorten will announce the plan in Perth on Wednesday.
The money will top up the $1.6 billion Fair Share for WA Fund announced last year, which was promised as a plan to lift the state's GST share to a 70 cent in the dollar floor.
Labor says the proposal does not change the current GST formula, but will end cross-country winner and loser arguments.
"We will help Western Australia without hurting the eastern states - with more money and more certainty for the future," he said in a joint statement with shadow treasurer Chris Bowen.
The coalition government has promised a Productivity Commission review of GST will be released this month which the opposition says it will consider.
Mr Shorten is also expected to match the Turnbull government's promised $3.2 billion infrastructure spend, the West Australian reports.