Actress Cynthia Nixon has been appointed to New York Mayor-elect Bill de Blasio's transition committee.

The Sex and the City star, who was an early supporter of the politician, will join 60 other community leaders to help de Blasio fill key positions in his administration and advise on policy ideas.

He says, "It is a group of people who share a progressive vision for the future of the city, who are known in their fields of endeavour as being effective and strong leaders, and who share a clear commitment to diversity in leadership for the future of the city."

The newly-appointed mayor takes office on 1 January (14).