Just three votes shy of an outright majority in a first round vote, Peres looked assured of winning an election he lost seven years ago after former parliament speaker Reuven Rivlin and Colette Avital extended their support.

"I am withdrawing from the race and call on all lawmakers to vote unanimously for Shimon Peres," said Rivlin choking back tears before the second round of voting began with the 83-year-old statesman the sole candidate.

"Long live the president of Israel," cried Rivlin, a hugely popular former parliamentary speaker whose father also ran for but lost the vote for the presidency conducted in the 120-member Knesset.

Senior Labour party MP Yoram Marciano waded in to announce "the party's unanimous decision to support the candidacy of Mr Peres."

The first round handed Peres 58 votes, Rivlin from the right-wing Likud party 37 and Labour MP Avital 21 after deputies came forward one by one, marked their secret ballot and dropped it into a black box by the speaker's chair.