The Republican chairman of the House Foreign Affairs Committee said Tuesday that the U.S. may need to impose economic sanctions against China to ensure that country puts the right kind of pressure on North Korea in the wake of its missile and nuclear testing.

Chairman Ed Royce, R-Calif., held a hearing Tuesday with officials from the Departments of State and Treasury, and agreed with comments from other lawmakers that the next step after this week's round of United Nations sanctions might be more economic pressure on China.

"It's been a long, long time of waiting for China to comply with the sanctions we pass and frankly with the sanctions that the United Nations passed," Royce said. "This is where the discussion needs to go next, if there isn't full compliance with the sanctions that the UN have passed, because what's at risk is our national security."

He was responding to complaints from Rep. Brad Sherman, D-Calif., who said sanctions against North Korea won't work as long as China is there to help the regime.

"We are not doing enough to force them to change their behavior, which is to punish North Korea a little bit for being a little bit too flamboyant in their actions, but to make sure that the regime can survive," Sherman said. "And this regime won't even agree to a freeze of their nuclear program unless you have something relatively, at least halfway, toward regime threatening sanctions."

China has thwarted U.S. efforts to crack down on North Korea's nuclear weapons program by refusing to fully implement various United Nations sanctions targeting the regime. That decades-old dynamic prompted a few lawmakers to suggest an aggressive policy of sanctioning China and eventually putting "regime-threatening" levels of pressure on North Korea.

Sherman argued for sanctioning China directly, rather than simply targeting individual companies that due business with North Korea.

"For 20 years, we've talked about company sanctions instead of country sanctions," he said. "For 20 years, China has carried out a policy where they smile at us, but they've done enough with North Korea so that [North Korea's] GDP is 50 percent higher in real terms. That's much better economic growth than we've achieved, so the sanctions have been not prevented a high level of economic growth."

A third member of the committee argued that a move to cut off trade with China finally might be the best non-military plan for preventing North Korea from obtaining the ability to strike the United States with a nuclear weapon, despite the economic damage that might do.

"If we did that, would it have an adverse impact on the American economy? Of course it would," Rep. Steve Chabot, R-Ohio, said during the hearing. "However, I would say that that pales in comparison to the impact on the American economy if we see a thermonuclear device go off in Seattle, or San Francisco, or [Los Angeles], or New York, or Washington."

A State Department official demurred when asked about the viability of such a tactic. "We are certainly looking at every option to put more pressure on China," Susan Thornton, the acting assistant secretary for East Asia and Pacific Affairs, told lawmakers. "As for cutting off trade, obviously, that would be a huge step and there are a lot of ramifications of that."

China is the United States' largest trading partner and the largest holder of American federal government debt. U.S. exports to China "supported an estimated 911 thousand jobs in 2015," according to the U.S. Trade Representative's office. The United States also imports more goods from China than any other country, so the affect of tariffs would be felt throughout the economy.

Sherman argued that presidents in both parties have taken the politically-easy course with respect to North Korea, rather than making unpopular decisions that might help solve the problem.

"For 20 years administrations have been coming here and telling me that we don't have to make any concessions to North Korea, we don't have to do anything that would make any single American company upset, and we're going to make the American people safe," he said. "But while we haven't made the American people safer, we've met the political objectives here in the United States. We don't threaten China even a little bit with country sanctions, because that would be politically difficult for the United States to do. We don't adopt reasonable objections, like a freeze in the North Korean program, because that would be politically difficult to do."