It is understood the federal government has made the decision in consultation with the chief medical officer Paul Kelly and the presiding officers, the Speaker of the House and the President of the Senate.

Prime Minister Scott Morrison has informed ACT Chief Minister Andrew Barr, who has been agitating for the next parliamentary sitting fortnight to be postponed.

The diagnosis of the 14-year-old daughter of Labor's finance spokeswoman and former ACT chief minister Katy Gallagher has led to an outpouring of sympathy and support, but has also prompted renewed concern about the safety of Parliament House.

Senator Gallagher was last in the building on Thursday, August 12. She has tested negative for the virus, is fully vaccinated and is in home isolation with her family.

The Prime Minister has offered his best wishes to Labor's Katy Gallagher and her family.

"I can understand she's terribly upset about the fact that one of her own children has been affected with Covid," he told reporters.

"Any parent, I can understand that, would be absolutely heartbreaking and I wish Evie and the family all the best for a speedy recovery."

The next parliamentary sitting fortnight falls within the two-week extension of the ACT lockdown.

While not sitting this week, and being closed to the public as part of a building lockdown, the people's house is operating with significantly reduced staffing levels as an essential workplace.

Out of concern that a sitting period could turn into a COVID-19 super-spreader event, the measures imposed on the building pre-date the ACT lockdown and have been more strict than required under ACT guidelines.

But Mr Barr has stated several times that now is "not the time" for Parliament to sit.

"They need to consider the urgency of a federal parliamentary sitting and whether it is required," he said.

"My preference would be that they don't, unless they absolutely had to. And if they did, it would need to be very minimal sitting and absolutely Covid-safe.

"But my starting point would be now is probably not the time for the Federal Parliament to return."

Parliament sat for a fortnight at the beginning of this month, with many MPs attending remotely via video link.

The Prime Minister has confirmed there are enough parliamentarians remaining in Canberra this week to form a quorum and allow Parliament to legally return when required, despite the lockdown requirements around the nation.

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