Trump says 'too bad' Israel headed for election rerun

US President Donald Trump said Thursday he was sorry to see Israel forced into an election rerun, after Prime Minister Binyamin Netanyahu failed to form a governing coalition.

"It's too bad what happened in Israel," Trump told reporters on the South Lawn of the White House.

"It looked like a total win for Netanyahu," he said, praising the Israeli leader as a "great guy." 

"They're back in the election stage. That is too bad."

Israeli Prime Minister Binyamin Netanyahu was confronted with one of the biggest defeats of his political career Thursday after failing to form a coalition and opting instead to hold an unprecedented second election.

Israel will now head to the polls again on September 17, just over five months after an April election that saw Netanyahu and his right-wing and religious allies win a majority.

Netanyahu was unable to convince ex-defence minister Avigdor Lieberman to abandon a key demand and join the government before a midnight Wednesday deadline.

Trump said another election is the last thing Israel needs.

"I mean they have got enough turmoil over there. It's a tough place. I feel very badly about that," he said.

Netanyahu's inability to form a coalition showed his long tenure atop Israeli politics may be weakening as rivals eye his downfall in the not-so-distant future over corruption allegations, some analysts said.