Agriculture Minister David Littleproud has asked the auditor-general to review taxpayer-funded water buybacks as Labor edges closer to supporting a major inquiry into a controversial $80 million purchase.
Mr Littleproud wrote to the auditor-general Grant Hehir on Tuesday asking him to look at water buybacks over the past decade.
"I'll be asking the auditor-general to look at all purchases of all political persuasions over the last period since 2008 to make sure that we can give confidence to the community," the minister told reporters in Tamworth.
Questions have re-emerged during the election campaign about a buyback of 28.7 gigalitres of water from two Eastern Australia Agriculture-owned Queensland properties, Clyde and Kia Ora, for $78.9 million.
Bill Shorten has hinted he would back a judicial inquiry into the issue, which has put then-water minister Barnaby Joyce under pressure.
The Labor leader said unless the Agriculture and Water Resources Department provided unedited documents about the buyback by 5pm on Tuesday, he would back a wide-ranging review.
"Not with a big texta marking out all the interesting details but the fair dinkum paperwork, without the redactions, without the secret squirrel business which this government loves," he told reporters in the central Queensland city of Gladstone.
Shadow treasurer Chris Bowen described the auditor-general review as a "cute little trick" to ward off unanswered questions about the water deal.
Scott Morrison insists the water buyback program has been run strictly within the rules and subject to regular reviews by the auditor-general.
The prime minister dismissed suggestions there was anything wrong with Eastern Australia Agriculture donating $55,000 to the Liberal Party four years before the sale.
The Greens have pushed for a royal commission into the Murray-Darling Basin Plan over the water buyback.
But the government has rebuffed those calls, arguing there is not enough evidence to necessitate a costly inquiry.
Mr Morrison is confident Mr Joyce acted appropriately despite questions over the high price and the company's links.
"The minister has acted in accordance with the legislation," Mr Morrison told ABC News Breakfast on Tuesday.
Mr Joyce is "100 per cent" confident the auditor-general will clear him of any wrongdoing, saying he had nothing to do with selecting the buyer or setting the price.
"I'm absolutely confident we have done absolutely nothing wrong," he told reporters in Tamworth.
Mr Morrison noted the previous Labor government had dealt with Eastern Australia Agriculture, citing a separate $300 million water purchase.
Labor argues the difference is that its buybacks were conducted through a competitive tender process.
Mr Morrison has also defended Energy Minister Angus Taylor, who was once a director of Eastern Australia Agriculture.
Mr Taylor co-founded the company that sold the water but said he'd had nothing to do with it since entering parliament and received no benefit from the sale.
Mr Joyce said the federal government had acted on a recommendation from the Queensland government, which confirmed it had supported the buyback.
Australian Associated Press