Peter Thomas Marshall Hill CB CVO is a British civil servant and a former political advisor. He was appointed CEO of the 26th United Nations Climate Change Conference of the Parties (COP26) in September 2019, having previously been Principal Private Secretary to the Prime Minister. Hill worked within Peter Mandelson's and his successor Catherine Ashton's cabinet when they were the European Trade Commissioner between 2006 and 2009. Hill was appointed Commander of the Royal Victorian Order (CVO) in the 2020 Birthday Honours for services to the Royal Household.