A legal challenge to the Australian-run detention centre on Papua New Guinea's Manus Island will face dismissal proceedings in court next month.
A Supreme Court judge Steven Cassman has ruled that the case will go before a three-judge panel after June the 24th.
The three are expected to decide whether the challenge, brought by the opposition leader, Belden Namah, can go ahead.
Lawyers for the government of Peter O'Neill filed an objection to Mr Namah's challenge last month.
The Australian government says it expects to start construction of a permanent detention facility on Manus in July.
More than 270 asylum seekers are being housed in widely-criticised conditions at a temporary facility at Manus' Lombrum Naval base.