Israeli Prime Minister Benjamin Netanyahu's battle for political survival looks set to stretch on for days or weeks after exit polls showed the Israeli general election is too close to call.

The surveys by Israeli television stations gave Mr Netanyahu's right-wing Likud 31-33 of parliament's 120 seats, compared with 32-34 for the centrist Blue and White led by former general Benny Gantz.

They indicated that Mr Netanyahu's ally-turned-rival, ex-defence minister Avigdor Lieberman, could be the kingmaker, with the backing of his far-right Yisrael Beitenu party critical to the formation of any ruling coalition.

"Netanyahu has lost, but Gantz hasn't won," said Udi Segal, a prominent Israeli television news anchor.

Without Mr Lieberman's support, the polls suggested, Likud could put together a right-wing coalition controlling only up to 57 parliamentary seats, while Blue and White could enlist no more than 58 legislators - meaning both parties falling short of the 61 needed for a governing majority.

Mr Lieberman was forecast to capture 8-10 seats, up to double his current tally in parliament, making him the linchpin.

Benny Gantz and his wife Revital cast their votes

The election was called after Mr Netanyahu, 69, failed in efforts to cobble together a coalition following an April ballot in which Likud and Blue and White wound up in a dead heat, each taking 35 parliamentary seats. It is the first time Israel has had two general elections in a single year.

The two main parties' campaigns pointed to only narrow differences on many important issues: the regional struggle against Iran, the Palestinian conflict, relations with the United States and the economy.

An end to the Netanyahu era, after a decade in power, would be unlikely to bring about a significant change in policy on hotly disputed issues in the peace process with the Palestinians that collapsed five years ago.

Mr Netanyahu, Israel's longest-serving prime minister, has announced his intention to annex the Jordan Valley in the occupied West Bank, where the Palestinians seek statehood.

But Blue and White has also said it would strengthen Jewish settlement blocs in the West Bank, with the Jordan Valley as Israel's "eastern security border".

The Palestinians and many countries consider the settlements to be illegal.