Jeff Seldin and Ken Bredemeier contributed to this report.
WASHINGTON - U.S. Secretary of State Mike Pompeo on Sunday staunchly defended the drone attack that killed top Iranian general Qasem Soleimani, but refused to publicly offer any evidence supporting the American claim that he posed an imminent threat to U.S. forces and officials in the Mideast.
Pompeo, in one of a string of interviews on news talk shows, told ABC that senior U.S. leaders who had access to all of the intelligence before the attack on Soleimani had "no skepticism" about the necessity of killing him.
"The intelligence assessment made clear that no action allowing Soleimani to continue his plotting and planning, his terror campaign, created more risk than the action that we took last week," the top U.S. diplomat said. "We reduced risk."
FILE - In this Sept. 18, 2016 photo released by the office of Iran's supreme leader, Revolutionary Guard Gen. Qassem Soleimani, center, attends a meeting with Supreme Leader Ayatollah Ali Khamenei in Tehran.
But Pompeo several times declined to reveal evidence of the threat the U.S. believed that Soleimani posed.
"There are simply things we cannot make public," Pompeo told Fox News. "You've got to protect the sources providing the intelligence."
On CNN, Pompeo said U.S. officials would continue to disclose information about the drone attack, but only "consistent with protecting our sources and methods and importantly our capacity to continue to understand what's going on in presenting threats. You don't want to risk that intelligence."
The war of threats between Washington and Tehran in the aftermath of Soleimani's killing was unabated.
U.S. President Donald Trump tweeted Saturday that the U.S. has identified 52 sites in Iran, including "some at a very high level & important ... to the Iranian culture," that the U.S. would strike "very fast and very hard" should Iran attack any U.S. personnel or assets in retaliation for the killing of Soleimani. The number 52 represents the 52 American hostages taken by Iran in 1979 and held for 444 days.
Under the Geneva Conventions laying out the legal constraints of war, attacking another country's cultural sites is a war crime. But Pompeo, while not rebuking Trump's Twitter comment, told ABC, "We'll behave lawfully. We'll behave inside the system. Every target that we strike will be a lawful target and it will be designed at the singular mission of protecting the American people."
Iranian supreme leader Ayatollah Ali Khamenei has vowed "severe revenge" against the killing of Soleimani. His top military adviser, Brigadier General Hossein Dehghan, told CNN, "The response for sure will be military and against military sites."
Iran's Foreign Ministry spokesman Abbas Mousavi said in a televised news conference, "Iran is not seeking a war but is ready for any situation." He said the final decision in response to Soleimani's killing would be made by "the system's leadership."
He said Iran would try to "devise a response in a way that would both make the enemy regret" Soleimani's killing and "not bring the Iranian nation to a war."
In this photo provided by ISNA, the flag-draped coffins of Gen. Qassem Soleimani and his comrades who were killed in Iraq in a U.S. drone strike, are carried on a truck surrounded by mourners during their funeral in Ahvaz, Iran.
Tehran said a million people poured into the streets of Mashhad, the country's second city, to mourn Soleimani's death. Because of the ongoing program there, authorities canceled a planned event in Tehran, instead urging Iranians to attend a ceremony honoring Soleimani at Tehran University on Monday.
In the U.S., Republican lawmakers voiced support for Trump's order to kill Soleimani. But opposition Democrats said that while they believed that Soleimani was responsible for the deaths of hundreds of U.S. forces in the Mideast, Trump's action increased the threat of a U.S.-Iran war and complained that a military intervention like that against Soleimani required congressional approval.
Sen. Chris Van Hollen told Fox, "We're now headed very close to the precipice of war." He said that "you just can't go around and kill" world figures the U.S. opposes. "The president is not entitled to take us to war" without congressional authorization."
Larry Pfeiffer, the director of the Hayden Center for Intelligence, Policy and International Security at George Mason University and a former senior director of the White House Situation Room, rebuked Trump's threats against Iranian cultural sites. He told VOA, "This is not how America should behave and would likely violate international conventions and norms." Pfeiffer said Trump's threats "sound like something that would be issued by an autocratic regime like North Korea."
"When the U.S. president makes it open season on cultural sites, he offers false justification to adversaries to do the same," Pfeiffer said.
Trump said Friday that Soleimani's killing was long overdue.
"We took action last night to stop a war," Trump said at his Mar-a-Lago resort in Florida. "However, the Iranian regime's aggression in the region, including the use of proxy fighters to destabilize its neighbors must end and it must end now."
Trump claimed Soleimani was responsible for the deaths of thousands of Americans, Iraqis and Iranians, saying the longtime Iranian general "made the death of innocent people his sick passion" while helping to run a terror network that reached across the Middle East to Europe and the Americas.
Analysts say any retaliatory actions against the U.S. by Iran would likely come after the three days of mourning that were declared Friday.
On Saturday, the White House formally notified Congress of Friday's drone strike. Under the War Powers Act, the notification is required within 48 hours of introducing U.S. forces into an armed conflict that could lead to war.
The classified document was sent to congressional leadership, officials said. It would likely describe the Trump administration's justifications for the strike against Soleimani, as well as intelligence information behind the decision and the expected scope of the military involvement. It is not known if the information will be released to the public.
Soleimani's body is being moved late Sunday to Tehran, before he is buried Tuesday in his hometown of Kerman.