Pavlopoulos announced Thanou's appointment after parliament's three largest parties failed to find coalition partners. The last to hold the mandate to form a government was Lafazanis, who created the new Popular Unity Party last week after splitting from Syriza, which he co-founded. This week, 53 of the 201 members of the Central Committee of Syriza submitted their resignations and joined Popular Unity. These dissidents have vowed to reject the new rescue agreement.
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It's expected that after the elections, Lafazanis will become the regulator of the political developments, as he will be the main critic of the austerity program, especially if his party takes third place in the elections.
Currently, there are no credible opinion polls in Greece to gauge how the political landscape will shift after the elections. Many political analysts predict that the New Democracy Party and Syriza will compete for first place. Regardless, Lafazanis, will be an ardent political opponent of the new Greek coalition government.
In an exclusive interview with CNBC, Lafazanis discussed his political views. "We aim to continue the radical commitments of Syriza," he said. "We are against privatizations, tax increases and pension cuts. If it is necessary to leave the euro zone and re-establish a national currency to end European subordination we will."
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The top of the party's agenda is to restore salaries and pensions to levels before 2010, as well as nationalize banks and private monopolies.
The factions that have emerged in Parliament threaten to gridlock the political process in Greece. Although Tsipras is expected to win the next election, it is unclear if he can secure enough parliamentary seats to govern alone. He has ruled out a coalition with any centrist opposition parties including PASOK and New Democracy, or the new Popular Unity Party.
—With additional reporting by Nasos Koukakis, special to CNBC.com