Ed Miliband

When Brown became Prime Minister in 2007, he appointed Miliband Minister for the Cabinet Office and Chancellor of the Duchy of Lancaster. Miliband was subsequently promoted to the new post of Secretary of State for Energy and Climate Change, a position he held from 2008 to 2010. After the Labour Party was defeated at the 2010 general election, Brown resigned as Leader of the Labour Party; in September 2010, Miliband was elected to replace him.

His tenure as Labour leader was characterised by a leftward shift in his party's policies under the "One Nation Labour" branding, and by opposition to the Conservative–Liberal Democrat coalition government's cuts to the public sector. Miliband also abolished the electoral college system to elect the leader and deputy leader of the Labour Party, and replaced it with a "one member, one vote" system in 2014. He led his party into several elections, including the 2014 European Parliament election.

Following Labour's defeat by the Conservative Party at the 2015 general election, Miliband resigned as leader on 8 May 2015. He was succeeded following a leadership election by Jeremy Corbyn, and returned to the backbenches. In 2020, Keir Starmer appointed Miliband Shadow Secretary of State for Business, Energy and Industrial Strategy, and later Shadow Secretary of State for Climate Change and Net Zero in 2021.

Following Labour's victory in the 2024 general election, Miliband returned to government after being appointed Secretary of State for Energy Security and Net Zero by Starmer.