Senate President Stephen Parry has offered to investigate potential conflicts of interest held by a coalition senator, but says he has received no formal request.
Labor wrote to Prime Minister Malcolm Turnbull and government leader in the Senate George Brandis in August about a number of potential conflicts held by Queensland Liberal National Party senator Barry O'Sullivan.
However, Labor senator Murray Watt told a Senate estimates committee on Monday he had yet to hear back from the government on what action would be taken.
"I expected some sort of response or action," Senator Watt said.
Senator Parry said he had not received any request to investigate the matter, but would if more "context" was provided.
"You have to look at the broad context of what the questions are about. I would investigate and inquire of the committees," Senator Parry said.
Senate Clerk Richard Pye said standing orders were in place to deal with conflicts of interest.
"All senators should declare interests that are relevant to their work as senators including their work on committees," he said.
Mr Pye said owning shares in a company which was the subject of an inquiry "would make the standing order a relevant standing order", but the "bare ownership" of shares would not necessarily immediately raise a conflict of interest.
Senator Watt has raised concerns about Senator O'Sullivan's potential conflicts in relation to disaster relief payments, a Toowoomba road project and the cattle industry.
Senator O'Sullivan has publicly denied any conflict between his private commercial interests and his public duties.
