The UN Secretary General Ban Ki-moon plans to name New Zealand lawmaker David Shearer as UN mission chief in South Sudan.

 Ki-moon has sent a letter informing the UN Security Council of his intention to appoint David Shearer as head of the UN peacekeeping mission in South Sudan, succeeding Ellen Margrethe Loej of Denmark.

Shearer, a 59-year-old member of New Zealand's parliament, served as UN deputy envoy in Iraq from 2007 to 2009, following UN assignments in Afghanistan, Lebanon, Israel, Rwanda, Liberia and the Balkans.

The 15-member Security Council is expected to approve the appointment on Friday if there are no objections.

Ban said Shearer would bring to the role "extensive political and humanitarian experience." He is currently New Zealand's opposition Labour party spokesman for foreign affairs and was Labour party leader in opposition between 2011 and 2013.

The United Nations has some 14,000 peacekeeping troops in South Sudan.