TEL AVIV — Prime Minister Benjamin Netanyahu said Monday that he could not form a new government after President Reuven Rivlin asked him to try in the wake of a deadlocked election.

Netanyahu's decision to cut short his efforts leaves the country's political future — and his own — uncertain.

The opportunity to form a stable government will now fall to his rival Benny Gantz, who leads the main opposition Blue and White party.

Rivlin tweeted that he would "transfer the mandate" to Gantz and "make available the 28 days allocated under the law."

Netanyahu needed the support of a 61-seat majority in Parliament, but his right-wing block had only 54 and he wasn’t able to get any left-wing party members to join him.

Netanyahu blamed his failure to form a government on Gantz.

“Tonight, I announced that I was returning the mandate to the Cabinet assembly," Netanyahu said in a video he posted on Facebook.

"That's what the people want. This is also what Israel needs in the face of growing security challenges. Over the past few weeks, I have made every effort to bring Benny Gantz to the negotiating table to prevent new elections. Unfortunately, time after time, he simply refused.”

After inconclusive election results left him short of the governing majority needed to extend his decadelong hold on Israeli politics, Netanyahu's right-wing Likud Party entered talks to form a national unity government with the centrist Blue and White.

Gantz — who is a former army chief of staff — had publicly resisted the idea of allying with Netanyahu, citing looming corruption charges against him.

Gantz's Blue and White party said in a short statement on Monday night that "now is the time of action."

"Blue and White is determined to form the liberal unity government, led by Benny Gantz, that the people of Israel voted for a month ago," it said.

If Gantz fails to form a government, Israel might have to hold its third national election of 2019.

Paul Goldman reported from Tel Aviv, and Max Burman from London.