U.S. President Donald Trump on Saturday said he had spoken with Israeli Prime Minister Benjamin Netanyahu on the phone about a possible mutual defense treaty. The move could bolster Netanyahu’s re-election bid just days before voters head to the polls. Trump provided no details, but a mutual defense treaty could obligate the U.S. to come to Israel’s defense if it is attacked. The U.S. President made the announcement in a tweet. Netanyahu then thanked Trump, saying that Israel “has never had a greater friend in the White House.” The timing of Trump’s tweet appeared to be aimed at helping boost Netanyahu’s bid to remain in power. Polls show a close race between his Likud party and the centrist Blue and White party led by former armed forces chief Benny Gantz. This will be Israel’s second election this year after Netanyahu declared himself the winner in April elections but failed to put together a coalition government.