Australia foreign chief stands in for PM after deputy ousted

Foreign Minister Julie Bishop will stand in as Australia's acting prime minister while Malcolm Turnbull conducts an overseas trip, following the dual citizenship crisis that has sidelined his deputy.

Australia's High Court on Friday disqualified Deputy Prime Minister Barnaby Joyce and four other senators from sitting in Parliament after they were each found to hold citizenship of Australia and another country.

Speaking to reporters in Sydney before a visit to Israel, Turnbull says Bishop, as deputy leader of the Liberals, was next in line after Joyce to be acting prime minister, and would fulfil that role during his trip.

Turnbull also says his coalition still holds a one-seat majority in the House of Representatives, where parties form governments.