WASHINGTON (Reuters) – President-elect Donald Trump’s incoming national security adviser, Mike Waltz, said on Sunday that if Hamas reneges on the Gaza ceasefire-for-hostages deal, the United States will support Israel “in doing what must be done.”

He added in an interview on CBS’ “Face the Nation,” “Hamas will never govern Gaza. That is absolutely unacceptable.”

Waltz said Trump and his team briefed Israeli Prime Minister Benjamin Netanyahu, adding “I want the people of Israel to hear me loud and clear.”

“If Hamas reneges on this agreement and Hamas backs down, moves the goalpost, what have you, we will support Israel in doing what needs to be done,” he said.

Waltz is also optimistic about the Trump administration being able to work out a normalization deal between Israel and Saudi Arabia as part of the Abraham Accords.