Former U.S. ambassador to the United Nations John Bolton said Sunday that economic sanctions against North Korea is a useless gesture, because North Korea is more like a huge prison than a real country that can be hurt by sanctions.

"It's a 25 million person prison camp," he told Fox News.

"The sanctions simply give people a warm and fuzzy feeling that we're doing something about North Korea. We are not," he said.

"If this administration follows the same policies as Clinton, Bush, and Obama administrations of carrots and sticks, and efforts to persuade North Korea, it will fail just like they did," Bolton added.

North Korea's aggression continues to pose real problems for the U.S., which many agree shouldn't risk a military strike because it would put at risk millions of people in South Korea and Japan.

Most see military action as a last resort, and are hopeful that some kind of sanctions program could work, despite Bolton's skepticism.

Treasury Secretary Steven Mnuchin on Sunday proposed ending trade with any country that deals with North Korea.

Sen. Ben Cardin, D-Md., said Monday that military options are limited, and also said President Trump needs to reach out to China and others.

"What the president needs to do is engage China and hopefully Russia to put the type of pressure on North Korea that changes their calculations," he said.

Former Rep. Jason Chaffetz, R-Utah, said he agrees sanctions won't do much

"You have to talk the language of the North Koreans, and that is force," he said.

Rep. Pete Sessions, R-Texas, agreed Monday that sanctions pressure is needed, but that the U.S. needs to prepare for something worse. When asked if he feared the repercussions of sanctioning China, he said, "Sure I am."

"But which one is greater to do?" he asked. "Some opportunity to send a strong signal to the Chinese that we intend to move them further into the international community, to protect peace and economic opportunity, or to simply rain down missiles upon North Korea?"

"I think I'll take the first one first," he said.