Deputy Liberal leader Julie Bishop will be acting prime minister while Malcolm Turnbull is overseas next week.

The foreign minister will fill the role instead of Nigel Scullion, who is acting parliamentary leader of the Nationals while Barnaby Joyce recontests his seat of New England after his expulsion from parliament.

Mr Turnbull will on Saturday leave for Israel, where he will attend the commemorations of the centenary of the Battle of Beersheba.

"Barnaby Joyce remains the leader of the federal Nationals but he is not currently in the parliament," Mr Turnbull told reporters in Sydney on Saturday.

"Therefore the normal order of precedence in terms of acting prime minister falls to Julie Bishop as deputy leader of the Liberal Party and foreign minister."