Bulgaria will head to the polls in July after the Socialists on Saturday became the third political party to refuse to lead a government following last month's parliamentary election. The Socialists, who lost almost half of their seats in the April 4 election, said it would be impossible to build a working majority in a fragmented parliament and would return the mandate immediately after the president hands it to them on May 5. President Rumen Radev faces having to dissolve parliament, appoint an interim administration and call snap polls within two months - most likely on July 11. Prolonged political uncertainty could hamper the European Union's poorest member state's ability to restart its pandemic battered economy and effectively tap the EU's €750 billion ($896 billion) coronavirus Recovery Fund. The Socialists' decision comes after both the centre-right GERB party of outgoing, three-time Prime Minister Boyko Borissov and the new anti-establishment ITN party, led by TV host and singer Slavi Trifonov, both gave up on attempts to form a government. Popular anger against widespread corruption after almost a decade of Mr Borissov's governance has boosted support for the anti-elite ITN party and two smaller anti-graft groupings, though the three together lack a majority in the chamber. The Socialists, who have campaigned to unseat Mr Borissov's GERB, said the three new parties have refused to enter into alliance with them.<br/> "The three new parties in the parliament showed political immaturity, they could not overcome their ego," Socialist leader Kornelia Ninova told reporters after a party meeting. "In this situation, despite our will for a change a government led by us, even a temporary one, is impossible."