Republican presidential Donald Trump on Monday suggested that the U.S. should defend Saudi Arabia in its escalating dispute with Iran only if the Saudis pay us back economically.

In an appearance on Fox News Monday evening, Trump told host Bill O’Reilly that in order to stop Iran from taking over Saudi Arabia from its borders with Yemen, the U.S. will be left with no choice but to side with the Saudis. “Frankly, the Saudis don’t survive without us. And the question is, at what point do we get involved, and how much will Saudi Arabia pay us to save them? Because that’s ultimately what’s going to happen,” said Trump. “I would want to help Saudi Arabia. I would want to protect Saudi Arabia. But Saudi Arabia is going to have to help us economically. They were making – before the oil went down – a billion dollars a day.”

But Trump fended off questions whether he would send U.S. troops to help fight off an Iranian incursion if the Saudis pay for some of the costs. “We already defend Saudi Arabia, right now, we’re defending them. Every time there’s a problem we go in and defend. And frankly, as far as I’m concerned, that’s all fine. We owe $19 trillion. We’re defending everybody. We’re defending the world. We can’t continue to defend everybody, and lose on every single thing we do,” he stressed.” We have to rebuild our country. Our country is a mess. Our infrastructure’s crumbling. We owe $19 trillion.”

The Republican presidential frontrunner also refused to commit taking military action against Iran. Instead, he blasted the nuclear deal with Iran, suggesting the regime has already violated the agreement by its testing of ballistic missiles. “The deal we made with Iran is a disaster. The deal we made for $150 billion is a total disaster,” he said. “Iran is going to have a nuclear weapon very soon.”

Asked if he would scrap the nuclear deal or strike Iran’s nuclear facilities, Trump responded, “I’m going to do what’s right. I want to be unpredictable. I’m not going to tell you right now what I’m going to do… We have to show some unpredictability. I want to be unpredictable. I don’t want to tell you exactly what I’m going to do.”

Other Republican candidates have also suggested that the U.S. should pick a side in the conflict and defend the Saudis if necessary.

Republican presidential hopeful Marco Rubio, during a campaign event in New Hampshire on Monday, said that while Saudi Arabia isn’t perfect, “they’re not an enemy of the United States.”

“Now there are things they do I’m not in favor of and I have strong problems with, but, that being said, they have been a military ally of the United States in that region,” Rubio asserted. “Iran has been our enemy.”

Saudi Arabia’s human rights issues is not a reason “for us to toss them under the bus,” added Carson in an interview on CNN. “I have a strong feeling that if, you know, our traditional allies in the region had full faith and confidence in us that we wouldn’t, like, turn our backs on them like we have on Israel; I think they would be much more enthusiastic about supporting anything that we called for,” he added.