A radical left-wing party vowing to end Greece’s painful austerity programme won a historic election victory, setting the stage for a showdown with the country’s international creditors that could shake the eurozone.

Greece’s splintered political landscape means small, often relatively new parties may determine whether the winner of elections next month can cobble together a lasting government and avoid a new financial crisis.

A pensioner has been hailed as a “martyr for Greece” following his suicide outside parliament.