TPV holders could be source of alienation

Australia faces a big challenge to ensure refugees on temporary protection visas don't become a source of social alienation, the immigration department head has warned.

Department secretary Michael Pezzullo told a Senate estimates hearing in Canberra on Monday that he hopes people can be integrated into communities while they are allowed to remain in Australia for three years.

Since TPVs were reintroduced late in 2014 only five had been granted up to mid-April as the government deals with a backlog of 30,000 asylum seeker cases inherited from the previous Labor government.