Maria Ohisalo announced she will not seek a further term as Green Party chair at a press conference on Tuesday.
The party lost seven seats in parliamentary elections on 2 April, dropping from 20 to 13 MPs.
The Green Party will elect a new chair at their party conference in June.
"I think it is better for the party that new leadership starts the recovery," Ohisalo told reporters, adding that she had already been in the party's leadership for the past eight years and wanted to make space for new faces.
Ohisalo summed up the last four years at the party's helm.
"It's never been an easy path for those advocating change," Ohisalo remarked.
Ohisalo said she takes full responsibility for the election defeat and that it is now important for the party to pause and reflect on its mission.
"The Green Party is at a crossroads. This election result was a big defeat," said Ohisalo.
Green government ambitions
Despite the election loss, the Green Party has not ruled out entering government.
Ohisalo told journalists that she intends to steer the party through negotiations to enter government as she is planning to work as party chair until a new leader is elected this summer.
Ohisalo previously said that the Green Party has a high threshold to enter a coalition, but that Finland still needs a functioning government.
"The Green Party is available if the future government starts to promote policies that do not cut a single euro from education, do not compromise on climate action and do not increase inequality," Ohisalo noted.
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