Greece is heading for a clash with international lenders as the radical leftwing party that came second in the weekend’s elections called for the ripping up of a “barbarous” austerity programme underpinning its bailout and questions mounted about the country’s future inside the euro.

Alexis Tsipras, the 38-year-old leader of the Syriza party that surged in popularity in Sunday’s poll, outlined a five-point plan to be put to conservative and socialist leaders today as he attempts to build a coalition, demanding the reversal of fiscal and structural measures that have enabled Greece to slash its budget deficit.

However, in an unusually blunt intervention, J?rg Asmussen, a European Central Bank executive board member, for the first time raised the possibility of a Greek exit from the euro – an option the ECB had previously refused to acknowledge in public.