Just hours before the United States announced a historic agreement on Iran's nuclear program, Gov. Scott Walker (R) weighed in on the negotiations on "Hannity." 

Walker said if elected president, he would make it clear that the U.S. should not be "in business" with the Iranian regime. 

"As President, on my very first day going forward, I would pull back – I would terminate that bad deal with Iran completely on day one. I would then put in place crippling economic sanctions against Iran, and I’d convince our allies that this is not a country we should be doing business with," he said.

Hannity asked Walker what he thinks about President Obama negotiating with a country that supports the destruction of Israel. 

"This is one of the biggest disasters of the Obama-Clinton doctrine," said Walker, adding that he does not believe Tehran is "substantively different" than in 1979 during the hostage crisis.

President Obama announced the agreement this morning, promising that it will prevent Iran from obtaining nuclear weapons and pledging to veto any legislation that attempts to block the deal.

Watch the clip below.