Shorten steps up Sinodinos attack

Labor has stepped up its attack on the Abbott government over Assistant Treasurer Arthur Sinodinos' links to a corruption inquiry, calling on the prime minister to immediately explain what action he intends to take.

Opposition Leader Bill Shorten has described as "most serious" the matters raised at the NSW Independent Commission Against Corruption inquiry in Sydney on Monday.

"I believe the prime minister should address this matter today," he told reporters in Canberra ahead of parliamentary question time on Tuesday.

"The prime minister needs to explain what course of action he intends to take."

There was significant community interest in the matter and it should not be allowed to drag on, Mr Shorten said.

Senator Sinodinos has been dragged into the ICAC inquiry into a business deal involving former state Labor powerbroker Eddie Obeid.

The inquiry has heard Senator Sinodinos - who in 2008 was a member of the board of Australian Water Holdings - stood to gain up to $20 million if the deal between the privately-held AWH and state-owned Sydney Water went through.

The senator, who is due to appear before ICAC as a witness at a later date, has denied any wrongdoing.