Benjamin Netanyahu held emergency meetings with the leaders of the coalition parties on Wednesday in an attempt to ward off early elections.
Some Yesh Atid and Hatnuah MKs are calling for their parties to leave the coalition over the lack of any progress in the peace talks and the prime minister's decision not to back conversion reform.
On Tuesday evening, Mr Netanyahu tried to quell the unrest, saying: "The last thing we need now is elections. The state of Israel needs a stable, strong and responsible government, and I call on all the members of the coalition to work together."
But the prime minister himself has already started preparing for elections in 2015 - at least a year and a half before the Knesset ends its full term - by calling for early leadership primaries in Likud.
In what was seen as an attempt to ensure support for a future coalition, Mr Netanyahu notified Hatnuah leader Justice Minister Tzipi Livni that the government would not support her party's proposal for a major reform of the religious giyur courts, which oversee conversions.
The PM has started preparing for an early election
The conversion reform has come in for heavy criticism from strictly-Orthodox rabbis and the Charedi parties that are not currently in the coalition. However, Mr Netanyahu would like the Charedi groupings in his next government, as he does not see their leaders as threatening his position as prime minister.
The decision not to back conversion reform has angered Hatnuah MKs, some of whom are calling on Ms Livni to leave the government.
The justice minister has so far rejected those calls and has vowed to continue fighting for conversion reform in the Knesset.
Mr Netanyahu's decision, however, has brought the two centrist parties together, and Ms Livni and Yesh Atid leader Yair Lapid announced over the weekend that they were forming a "joint front" in the government to call for renewed talks with the Palestinians and more reforms of the ties between the state and the religious establishment.
Mr Lapid denied that his party was interested in leaving the coalition, saying that "there is no crisis and no need for early elections".
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