Washington (CNN)An attack by terrorists on the United Kingdom is "highly likely" -- though it has existed for more than a decade -- British Prime Minister David Cameron says.
Cameron, Rubio: Terrorism threat growing
"The threat has changed and altered, but it's still based on the fundamental problem of a poisonous death cult narrative, which is the perversion of the world's major religions, and that's the thing we're still up against," Cameron said in an interview aired Sunday on CBS' "Face the Nation."
He said he won't use the word "war," as French President Francois Hollande did, to describe the effort to prevent terror attacks because "we do not want to help them in their narrative by saying it's a war of us against them."
But he said faltering governments in Iraq and Syria have fueled the threat, and especially ISIS in the region.
"We need functioning government in Iraq, functioning government in Syria, to be the legitimate authorities that with us, help to stand back this perversion of the Islamic religion," Cameron said.
The prime minister was in Washington to visit President Barack Obama in recent days. His comments come after the attack on the Charlie Hebdo satirical magazine in Paris.
Sen. Marco Rubio agreed with Cameron's assessment of the terrorism threat, saying that "homegrown violent extremism" has increased the threat of another terrorist attack.
The Florida Republican and potential 2016 presidential contender made his comments during an appearance on "Face the Nation," as well. He said the threat now extends beyond Sept. 11, 2001-style attacks by foreigners.
"Some of these individuals that are plotting these attacks may not have even traveled to the Middle East. They've been radicalized at a local mosque or online, and they've received instructions and or inspiration about how to carry out these attacks on the West from online platforms," Rubio said.
"So I think that's a very real risk for Europe, which is closer to the Middle East, and has large immigrant populations from that region, but it's a real risk here in the United States, a country where every single year millions of people visit, travel to, immigrate to," he said.