In November 2024, he was announced as the UK National Security adviser, serving in Downing Street under British prime minister Keir Starmer.

[3] In 2024, UK Prime Minister Sir Keir Starmer appointed Powell as a special envoy to resolve the Chagos Archipelago sovereignty dispute.

[7] Following Labour's election victory in 1997, Powell was given the new official role of Downing Street Chief of Staff, a new position with the power to issue orders to civil servants, which was unprecedented for a political appointee.

[7] In the early years of the Blair Government, one of Powell's most crucial jobs was his role in the Northern Ireland peace talks that led to the Good Friday Agreement.

Powell continued to be both a key right-hand man for Blair throughout his time in office, as well as a trusted advisor on a wide range of policy issues.

He told a BBC documentary, Putin, Russia and the West, how MI6 had in 2006 used a "fake rock filled with surveillance devices as a means of communication with their agents in Moscow".

Oborne described this as a "propaganda gift for Vladimir Putin", as it soon after featured heavily in a programme screened on prime-time Russian state TV.

[17] In May 2014 British prime minister David Cameron appointed Powell as the UK special envoy to Libya to promote dialogue between rival factions in the country.

[18] In March 2017 he was appointed Honorary Professor in the Senator George J. Mitchell Institute for Global Peace, Security and Justice at Queen's University Belfast.

[19] In September 2024, Labour Prime Minister Keir Starmer appointed him as an envoy to negotiate with British Indian Ocean Territory and Mauritius regarding the Chagos Archipelago sovereignty dispute.

[23] Powell's role as Downing Street Chief of Staff came under close scrutiny during the Hutton Inquiry, held following the death of David Kelly in 2003.

An email sent by Powell to the JIC chairman John Scarlett in September 2002 was also highlighted, as it appeared to suggest that a dossier on the threat posed by Iraq should be toughened.