The NSW corruption watchdog says its high-profile inquiry into a company linked to Labor and Liberal figures including Arthur Sinodinos has not yet been completed, amid reports the Turnbull government minister has been cleared of corruption findings.
Senator Sinodinos, a former chairman of controversial infrastructure company Australian Water Holdings, was called as a witness during the Independent Commission Against Corruption's public inquiry into the company in 2014.
Submissions from counsel assisting the ICAC, sent on December 18 and apparently leaked to News Corp by a third party, have reportedly indicated that he will not face such a finding.
However, it is not yet clear whether the watchdog will make critical comments about his time as non-executive chairman of the company.
On Thursday, Senator Sinodinos told Fairfax Media he was not able to provide a comment until the inquiry was finalised.
Finance Minister Mathias Cormann told ABC Radio on Thursday it was "very difficult" to comment on the situation because the final report - expected around March - had not been officially released.
But Senator Corman praised his fellow frontbencher as a "friend and valued colleague".
"Arthur was only ever questioned as a witness," he said. "He was never a target of that investigation. "
The ICAC released a statement on Thursday morning stressing it had not finished its investigation.
A spokeswoman said the Commission had "invited further submissions from relevant parties in Operations Spicer and Credo [which involve AWH and Liberal Party donations] as a result of recent changes to the ICAC's jurisdiction.
"The submissions phase has not been completed. When it has, the commission will prepare and table a report to the NSW Parliament detailing its findings."
The High Court ruled in April last year that the ICAC did not have the power to investigate a range of allegations against private citizens where no wrongdoing was alleged on the part of a public official.
Laws to amend the ICAC's jurisdiction were rushed through the NSW Parliament to deal with the fallout from that ruling, but still left parts of Operations Spicer and Credo outside its jurisdiction.
The NSW senator has denied any wrongdoing but stood aside from the frontbench, explaining he wanted to avoid any distractions for the Coalition government.
He was reinstated to the frontbench as cabinet secretary by Prime Minister Malcolm Turnbull in September, amid expectations that he would be cleared.
A former chief of staff to prime minister John Howard, Senator Sinodinos was appointed to the AWH board in 2008 and made chairman in 2010, while he was honorary treasurer of the NSW Liberal Party.
The inquiry into AWH has probed a range of allegations, including that the company improperly billed the state-owned utility Sydney Water for lavish expenses, including limousines and airfares.
The inquiry crossed party lines and examined allegations that the family of disgraced former Labor minister Eddie Obeid had a secret $3 million stake in the company, although the Obeids have insisted the money was a loan.
Former NSW Labor ministers Joe Tripodi and Tony Kelly face allegations they misused their positions by changing a cabinet minute in an attempt to benefit the company.The men denied the claims.
After the March 2011 election that swept Labor from power in NSW, Australian Water assiduously lobbied the state Coalition government. The commission was also investigating whether Australian Water paid $183,000 to an alleged slush fund set up by a former adviser to former Liberal minister Chris Hartcher.
The company's former chief executive, prominent Liberal Party fundraiser Nick Di Girolamo, gave former NSW premier Barry O'Farrell the now infamous $3000 bottle of Grange that ended his premiership.
News Corp has reported that allegations of fraud relating to the expenses billed to Sydney Water will not be pursued against Mr Di Girolamo.
He had denied the claims and the subsequent High Court ruling on the ICAC's powers made it clear that allegations of fraud against private citizens generally will not be within the watchdog's jurisdiction.
However, he faces a potential allegation that he encouraged Mr Tripodi and Mr Kelly to change the cabinet minute to benefit the company.