"Ambassador Pedro Manuel Carqueijeiro Lourtie is appointed, on a proposal from the government, to the post of Permanent Representative of Portugal to the European Union," the decree said.
Between 2006 and 2009, Lourtie served as José Sócrates' chief of staff when he was prime minister, and then became secretary of state for European affairs.
In 2015 he was appointed Portugal's diplomatic representative in Tunis.
Pedro Lourtie has a degree in economics and is a career diplomat, having previously held posts at REPER and the EU representation in Washington.
The Official Gazette had published on Wednesday that Portugal would have new permanent representatives to the European Union in Brussels and to the Organisation for Economic Cooperation and Development (OECD) in Paris.
The official gazette indicated that ambassador Nuno Filipe Alves Salvador e Brito had been relieved of his post at REPER, but without giving details of the appointment of a replacement.