Jane Dodds has announced she will stand down as leader of the Welsh Liberal Democrats.
Dodds said she would remain the party's only Member of the Senedd (MS), but that work to increase its presence in Wales' parliament "should be led by a new generation".
"Leading the Welsh Liberal Democrats has been the honour of my life," she said in a statement on Tuesday, adding "now is the right time" to hand over the role.
Only Welsh Lib Dem MP David Chadwick is eligible to seek nomination to replace Dodds at this stage, the party said.
The Liberal Democrats have been represented by just one member in Cardiff Bay since 2016, initially by former Welsh Lib Dem leader Kirsty Williams and later Dodds since 2021.
Dodds, who represents Brycheiniog Tawe Nedd in the Senedd, is a former social worker who was made her party's Welsh leader in November 2017.
Nominations to replace her will open on 23 October and close on 16 November.
"After May's election, I've thought hard about what our party needs," she said.
"Wales needs more than one liberal voice in the Senedd.
"Building that team will take years of hard work in communities across the country, and I believe that work should be led by a new generation.
"Now is the right time to hand it over."
Paying tribute to Dodds, Welsh Liberal Democrat president Tim Sly said she had "led our party with warmth, determination and integrity through some of the most turbulent years in Welsh and UK politics".
"She leaves the Welsh Liberal Democrats stronger in our communities and ready to build," he said.
"On behalf of every member, I want to thank her for her extraordinary service."
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