The United States on Friday blocked the appointment of former Palestinian prime minister Salam Fayyad to be the new UN envoy to Libya.

US Ambassador Nikki Haley said in a statement that she did not "support the signal this appointment would send within the United Nations," where the state of Palestine does not have full membership.

UN Secretary-General Antonio Guterres had informed the Security Council this week of his intention to name Fayyad to lead the UN support mission in Libya and help broker talks on a faltering political deal.

Haley said the United States was "disappointed" to see the letter from Guterres, his first appointment of an envoy to a major conflict area.