Ann-Magrit Austenå, who heads the Norwegian organisation for Asylum seekers (Noas), said that a proposal to establish 'return centres' for those who have had their asylum applications refused "looked scary".
"What it opens up is a much-wider use of detention in Norway, " she told The Local. "I think there's a danger of establishing a practice where Norway will use detention more often than if Progress party wasn't in government. I'm afraid of that. That's why I'm trying to ring the alarm."
The proposal is one of several measures to tighten control of immigration included in the agreement Norway's Conservative and Progress parties, who are likely to form the new government, announced on Monday night. The deal was signed with the Liberal and Christian Democrat parties, who have decided not to join the coalition, in order to bind in their support for certain measures.
The parties propose to split Norway's existing reception seekers into ones for people who have had their applications accepted, who will prepared to enter Norwegian society, and ones for people who have been refused, who will receive no training.
As a result, Austenå expects the number of detention centres to increase dramatically.
"They want more detention centres around the country and not only Trandum, which is today the only detention centre in Norway for foreigners."
She said that the two parties did not need to change the law to do this, and would instead rely on agreeing new guidelines based reinterpretation of the existing legislation.
Austenå is one of several campaigners who worry publicly about how the inclusion in government of the populist Progress Party, which has a strong anti-immigration stance, will affect policy.
Rune Berglund Steen, who heads Norway's Centre against Racism, said that he was relieved by the party deal.
"I expected that the Progress Party would have achieved more. Of course there are things we don't like, but I think this is a fairly soft result," he told The Local. "The Progress Party have been able to put their footprint on it a little, but I would have expected worse."
Austenå also criticised a proposal in the four-party deal to insist that men or women who have successfully immigrated must wait until they are 24 years old before they can bring over their spouses and families, saying this would only add to the trauma faced by refugees.
"They will have to wait for years to get their families here, it's dramatic. We know that many of them need the stability of the family can provide," she said.
Meanwhile, campaigners pointed out that the small print of a much heralded amnesty for the children of failed asylum seekers meant that children from many countries would be excluded.