Alexis Tsipras annoucned Thursday he was stepping down as head of the Syriza party following a disastrous election defeat earlier this month.

"The time has come to start a new cycle," Tsipras said in a televised address from Athens. "The negative result can — and must — become the beginning of this cycle."

Leftist politician Tsipras was once one of Greece's youngest-ever prime ministers, leading the country during a period of ravaging austerity.

He said he will call "elections within Syriza for a new leader, in which I will not be a candidate."

Syriza was only able to gain around 18% of the ballots in the second round of voting, which saw the ruling center-right New Democracy party keep its majority in parliament, despite facing a number of scandals.

What is Tsipras' legacy?

The 48-year-old Tsipras held the office of prime minister from 2015 to 2019, a period that was marked mostly by the fallout of the financial crisis and the question of whether Greece would remain in the eurozone.

Tsipras had a fraught relationship with Germany due to disputes over the imposition of austerity measures to secure international bailouts.

Syriza had come to power on an anti-austerity pledge. However, under pressure from Germany and other wealthy EU countries, Tsipras' government ended up overseeing some of the deepest austerity measures in Europe — with his party plagued by resignations from senior members who opposed the new course.

After 15 years at the helm, Tsipras is the longest-serving leader in Syriza's history. He will stay on as leader of the party until a successor is found.

"This difficult journey had compromises, and difficult decisions, and injuries and attrition, but it was a journey that left a mark on history," Tsipras said during his resignation announcement.

ab/dj (Reuters, AP)