The WA Liberal Party has started its annual conference with attacks on coalition partners in the National Party, and Labor.
The 67th state gathering began with an address from State President Norman Moore.
Mr Moore attacked new Nationals' leader Brendan Grylls, saying his proposed mining tax would only benefit Brazilian iron ore producers.
Norman Moore hits out at the Nationals "weird Brendon". It's mining tax will only benefit the Brazilian miners @9NewsPerth— Josh Jerga (@josh_jerga) August 13, 2016
He also lashed out at state Labor leader Mark McGowan, labelling the Rockingham MP as "a boy on a man's errand".
The conference is being held in the Hyatt Regency Hotel in Perth.
Mr Grylls returned to the leadership of the WA Nationals on Tuesday and immediately outlined a plan to levy a $5 per tonne charge on iron ore miners BHP Billiton and Rio Tinto.
He said the move could raise more than $7 billion dollars in four years and bring the state budget back into surplus.
The plan was attacked by labor as being "financially illiterate".
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