A federal government senator has cast doubt on Scott Morrison's promise to expand the Northern Territory's Howard Springs quarantine centre.
The prime minister has pledged to lift the capacity from 850 to 2000 beds this month in a move crucial to allowing repatriation flights from India to restart.
The NT government has recruited less than half of the 400 staff it needs to manage Howard Springs when it takes over from the federal AUSMAT team now in charge.
NT Nationals senator Sam McMahon believes the capacity "absolutely can't" be lifted to 2000 beds because of the staffing shortage.
"It would be foolish to try and ramp up the facility to 2000 unless the required staff are there," she told reporters in Darwin on Wednesday.
Senator McMahon said she also had major concerns about transferring responsibility from the AUSMAT team to the NT government.
"It is an extremely well-managed and functioning facility under AUSMAT," she said.
"But I have received assurances from the Northern Territory government and also from federal minister Greg Hunt that AUSMAT will remain involved as long as they are needed to be involved."
NT Chief Minister Michael Gunner says Howard Springs is one of the best quarantine facilities in the world.
"We have recruited an extra 170 staff and are going to have an anticipated peak of 1200 people in our care during May," he said.
He said the additional 230 staff would be recruited in May from 2500 applicants to help with new arrivals, which are expected to reach 2000 people per week during June.
"There is a soft handover with AUSMAT. They are exceptional at their work and along with NT Health are one of the reasons Howard Springs is gold standard," he said.
There are 9000 Australians trapped in India, with 650 considered vulnerable, waiting for the government to lift the travel ban.
Chief Medical Officer Paul Kelly has warned some could die as a result of the flight pause, which he recommended was necessary to stop quarantine from being overwhelmed.
Mr Morrison expressed confidence in allowing the NT to take over Howard Springs during a visit to Darwin and surrounds last week.
"We wouldn't have entered into those arrangements were our expert advisers and medical experts not comfortable," he said.
Australian Associated Press