By Renee Maltezou and James Mackenzie
BRUSSELS/ATHENS (Reuters) - Greek Prime Minister Alexis Tsipras is set to begin a bruising week by clearing out party rebels opposed to an austerity package that will have to go through parliament within days, people close to the government say.
With Greece's future in the euro zone in the balance and European partners demanding immediate action to rebuild broken trust and prove his commitment to reform, the 40-year-old leftist prime minister cannot afford to wait.
To convince creditors to start talks on a third multibillion euro bailout package, Greece will have to pass laws by Wednesday night to cut spending, toughen value added tax, overhaul pension systems, change bankruptcy rules and advance privatisations.
However a mini-rebellion of lawmakers on Friday laid bare tensions in the ruling Syriza party. The revolt saw 17 deputies from the government benches withhold support in a vote to authorise bailout negotiations, leaving Tsipras reliant on opposition parties to pass the measure.
Dealing with the consequences of that revolt will provide a clear signal of how determined Tsipras will be in pushing through the reforms European partners are demanding.
Whether cooperation with opposition parties leads to a full-scale national unity government, with seats in the cabinet is still unclear but the change has left the future of the radical leftwing government in doubt. The government has 162 seats in the 300 seat parliament.
Among the most prominent rebels, Energy Minister Panagiotis Lafazanis, leader of the so-called "Left Platform" within Syriza and Deputy Labour Minister Dimitris Stratoulis, a former unionist and a fierce opponent of pension cuts, are expected to be sacked, people close to the government say.
The uncompromising speaker of parliament, Zoe Constantopoulou, who also defied Tsipras and abstained from the vote, would require a no confidence vote to be replaced but the other rebels would be expected to resign their seats, the same people say.
Under a Syriza party agreement, deputies are supposed to resign their seats if they publicly disagree with government policy although there is nothing to stop them refusing to stand down and holding on to their seats as independents.
Terence Quick, a member of the rightwing Independent Greeks, the junior coalition partner in the government, said that any deputies who voted against the government should resign.
"I don't think abstaining or being absent shows you are responsible or honourable in these particular circumstances. You either go in and say a forceful no and you leave or you say 'Yes' and you continue to fight," he said.
Clearing out the leftwingers still defending the anti-bailout platform on which Syriza won power in January would underline how seriously the situation has worsened for Greece in the past six months.
With the financial system on the brink of collapse and shuttered banks running short of cash, the six-year Greek crisis has escalated dangerously, forcing Tsipras to change course only a week after voters resoundingly rejected a milder package of bailout terms in a referendum.
There are also questions about how stable any such government would prove, given the deep ideological differences between Syriza and the centre-right New Democracy or Socialist Pasok parties.
Opinion polls suggest that Syriza remains by far the strongest party and the most likely winner of any new election, suggesting that any reshuffle may simply be the prelude to a deeper change later.
The Syriza party newspaper Avgi said that if Tsipras is not to become a "hostage", changes would have to be made.
"That raises the issue clearly of reshaping the government, of the government's majority, which leads to elections very soon," it said in an editorial on Sunday.
(Additional reporting by Costas Pitas; editing by Janet McBride)