Carla Denyer has announced she will not stand again as co-leader of the Green Party of England and Wales, saying she wants to focus on her role as an MP.
The MP for Bristol Central was one of four Greens elected in last year's general election – the party's best ever result.
She was elected by party members as co-leader alongside Adrian Ramsay in 2021.
On Monday current deputy leader Zack Polanski launched his leadership campaign, saying the party was sometimes "too polite" and needed to be "bolder".
The Green Party of England and Wales normally elects co-leaders every two years but Ramsay and Denyer were initially elected for a three-year term, with members then voting not to choose new leaders in 2024 because of the general election.
Nominations for the next contest open on 2 June, with party members voting throughout August before the results are announced on 2 September.
Under party rules, there can be one leader but if two co-leaders are elected they must be of different genders.
