An Iranian woman is among a group of 21 refugees who have reportedly left Nauru to the United States for resettlement.
The group, which included mostly Afghan men, one Rohingyan, one single Iranian woman, and a Tamil family, flew from Nauru on Sunday, refugee advocate Ian Rintoul says.
They are among some 130 refugees who will leave the island this month under Australia's resettlement deal with the US.
The single Iranian woman was the first Iranian to be accepted from Nauru or Manus Island for resettlement in the US in 2018, Mr Rintoul said.
But, he raised concerns about the "hundreds of refugees and asylum seekers" left with no future as the US deal soon comes to a close.
"For the majority of people dumped there, there is no end in sight," Mr Rintoul said.
"It's time to end the agony of indefinite detention and bring all the refugees and asylum seekers to Australia."
The US resettlement deal was struck between former president Barack Obama and Prime Minister Malcolm Turnbull, providing a path out of detention for refugees offshore, including at Manus Island and Nauru.
