Papua New Guinea's Supreme Court has directed lawyers for the government to file their position on the opposition's constitutional challenge against the Manus Island asylum seeker processing centre.
The opposition's first case against the Manus processing centre was thrown out of court on a technicality.
Since then, the opposition has relaunched a fresh challenge after the government agreed to an extended refugee resettlement arrangement with Australia.
Justice Steven Kassman on Tuesday directed the government's lawyers to file a statement on its position on the case by next Tuesday.
The opposition's lawyer says one of the detainees at the Manus centre, Rawed Reza, has contacted him seeking to join the challenge.
A decision on whether he is able to join is expected on September 10th when the court case will resume.