Greek Prime Minister Alexis Tsipras is set to call early elections, state television said on Thursday, in a bid to quell a mounting rebellion in his leftist SYRIZA party and seal support to implement a tough bailout program.

After days of rumors about what the government would do next, government officials said the previously cited option of a confidence vote had been shelved and the idea of calling snap polls as early as mid-September had become more likely.

Tsipras was huddling with senior advisers on Thursday afternoon to decide his next move, a government official said.

"Everything is possible," the official told reporters when asked whether Tsipras could announce elections later in the day.

ERT state television said the timing of snap elections would be announced later on Thursday.

Tsipras had been widely expected to call snap polls at some point in the autumn after a bruising seven months in office that saw Greece nearly crash out of the euro zone and shut its banks for three weeks to survive a battle with foreign creditors.

After campaigning against austerity, the 41-year-old leader last month accepted an 86 billion euro bailout package from European and International Monetary Fund creditors tied to tax hikes and spending cuts under the threat of a banking collapse.

But votes in parliament to pass the stringent austerity measures laid bare a revolt by nearly a third of SYRIZA lawmakers, forcing Tsipras to rely on opposition support and robbing him of a guaranteed parliamentary majority.

With the bailout approved in parliament and the first tranche of aid disbursed - allowing Greece to repay debt to the European Central Bank that fell due on Thursday - Tsipras can now focus on taking on far-left party rebels who have threatened to breakaway.

Energy Minister Panos Skourletis, a close Tsipras adviser, said the split had to be dealt with. "The political landscape must clear up. We need to know whether the government has or does not have a majority," he told ERT.

[Reuters]