WASHINGTON, Jan. 31 (Xinhua) -- An umbrella group known as the "Islamic Resistance in Iraq" was responsible for the drone attack last week that killed three U.S. soldiers in Jordan, the White House said on Wednesday.

National Security Council Coordinator for Strategic Communications John Kirby told a regular White House briefing that the attack, which also injured more than 40 U.S. service members, was "planned, resourced and facilitated" by the Islamic Resistance in Iraq, an umbrella group containing "multiple groups including Kataib Hezbollah."

Kataib Hezbollah is a militant group operating in Syria and Iraq that the United States has accused of being the perpetrator of repeated attacks on U.S. personnel and military facilities in the region in the aftermath of the Israeli-Hamas conflict.

U.S. forces have launched several counterstrikes against Kataib Hezbollah, which is considered by Washington as one of Iran's most powerful proxies.

For the attack on the U.S. base in Jordan, though, Kirby refrained from singling out Kataib Hezbollah when asked to be more specific about which exact group the United States would attribute the attack to.

"This certainly has the earmarks of the kinds of things that Kataib Hezbollah does," he said. "The attribution that our intelligence community is comfortable with is that this was done by the umbrella group called the Islamic Resistance in Iraq."

U.S. President Joe Biden said on Tuesday he had already made a decision on how to respond to the attack that caused first U.S. fatalities since the Israeli-Hamas conflict broke out on Oct. 7. He didn't elaborate, but reiterated that his administration is not looking for a "wider war in the Middle East."

Kirby said the U.S. response would be an "iterative process" instead of a "one-off" reaction. "This will be a response over time. You should expect that the president will continue to weigh options ahead of them," he added.