The journalist embroiled in the Peter Slipper sexual harassment case has been told to confirm whether he will break a confidentiality agreement by revealing documents in court.

News Limited reporter Steve Lewis has been ordered to produce communications he had with the Speaker's former staffer, James Ashby, before the harassment claims were made public in April.

Lawyers for Mr Slipper have tendered radio transcripts and a spreadsheet of text messages in the Federal Court in a bid to prove that Lewis cannot claim confidentiality in the case.

They told the court it is well-known that Mr Ashby was a key informant in the story.

But lawyers for the journalist disagree.

Alec Leopold SC said the material did not specify the staffer and that producing the document in question could identify a confidential source.

Justice Steven Rares stood the matter over until next week, saying the journalist needed to readdress whether he could serve the subpoena order.

While Mr Ashby has accused the sidelined Speaker of sexual harassment, both Mr Slipper and the Federal Government are trying to have the case declared an abuse of process.

They say Mr Ashby conspired with other staffers and Mr Slipper's political rivals to vilify him and ruin his career.

The court has previously heard allegations that Lewis sent one text message to a Slipper staffer saying: "We will get him."

Last week, a judge agreed that Mr Ashby did not have to put forward a defence to the abuse of process claims because he might be investigated for allegedly leaking pages from Mr Slipper's diary.