A Senate committee initially heard Nev Power would be paid $500,000 over six months to cover his travel and accommodation costs.

But the prime minister's department has corrected the figure to about half of that.

Mr Power's travel to Canberra from his Perth base has been estimated at about $6000 per return trip.

Accommodation, including incidentals like food and taxis, is estimated at $350 per night.

Government Senate leader Mathias Cormann said the costs were based on the Department of Prime Minister and Cabinet's estimates.

"He does come from Perth," he told parliament on Thursday.

"We are a big continent and people from Western Australia should also be allowed to participate in these sorts of processes."

Labor and the Greens pursued the pay of the former Fortescue Metals chief, questioning how it could be justified when millions of people were missing out on the JobKeeper wage subsidy.

"I can see there is an attempt here to smear a distinguished Australian who is providing great service to Australia," Senator Cormann said.

"He is doing an extremely important job for Australia as we ensure that we are in the best possible position to recover strongly on the other side."

Senator Cormann said neither the prime minister nor his office were involved in determining payments to Mr Power, who is not getting a salary on top of costs.

Australian Associated Press