Reps. Ed Royce (R-Calif.), left, and Eliot Engel (D-N.Y.) on Capitol Hill in Washington last year. (Manuel Balce Ceneta/Associated Press)

President Trump threw a wrench into his own plans to coordinate diplomatic action on North Korea last week when he started a new dispute with South Korea over funding for a joint missile defense program and threatened to scuttle the U.S.-South Korea free trade agreement. On Tuesday, congressional leaders will attempt to bring the focus back to where they think it belongs — increasing pressure on Pyongyang, not on U.S. allies.

On Sunday, national security adviser H.R. McMaster tried to smooth over the dispute by pledging that the United States will pay for the Terminal High Altitude Area Defense (THAAD) system “until any renegotiation.” Trump shocked South Korea last week by saying he would ask its government to pay for the anti-missile batteries. But the damage had already been done, as South Korea’s presidential candidates wondered why the U.S. president threatened a close ally without consultation and the leading candidate said the entire deployment must be reviewed.

The best way Trump can move past the rift is to refocus on sanctions against the North, according to congressional leaders. On Tuesday, Congress will begin debate on a bill meant to do just that.

“We’ve got to stand with our allies. There can’t be any daylight right now,” House Foreign Affairs Committee Chairman Ed Royce (R-Calif.) told me. “We need to be focused right now on what we can do to unify a position in the international community to put the ultimate pressure on North Korea.”

There will be plenty of time later for negotiations over how the United States and South Korea should share the financial burden for joint defense, Royce said.

“Right now, at the present time, our focus needs to be on deterring this growing threat coming from North Korea,” he said. “So now is not the time to enter negotiations on that issue.”

Royce said the administration should work not only with allies but also with Congress to implement the strategy that a new U.S. government policy review came up with, called “maximum pressure and engagement.” The House of Representatives will vote on the new North Korea sanctions bill later this week.

The legislation, called the “Korean Interdiction and Modernization of Sanctions Act,” is sponsored by Royce and the committee’s ranking Democrat, Rep. Eliot Engel (N.Y.), and is expected to pass easily. It would greatly expand the president’s authority to increase sanctions on North Korea and also punish countries and entities that aid the North Korean regime or fail to enforce United Nations Security Council resolutions.

The bill would increase sanctions on financial institutions all over the world that still do business with North Korea and target foreign ports through which the North Korean government ships goods. The bill would also sanction any businesses that benefit from the use of North Korean forced labor.

The legislation would also require the State Department to examine whether to put North Korea back on its list of state sponsors of terrorism. The George W. Bush administration removed Pyongyang from the list in 2008 as part of a previous nuclear disarmament agreement. Last month, the House overwhelmingly passed a resolution calling for the State Department to determine whether the Kim regime should be placed back on the list, following the assassination of Kim Jong Un’s half brother Kim Jong Nam in Malaysia with a chemical nerve agent.

Royce, who has a large Korean American constituency in his district, has authored several pieces of North Korea sanctions legislation over the years. He was a huge supporter of the U.S.-South Korea free trade agreement and has met several times with defectors from Pyongyang, including as recently as two weeks ago.

Cutting off the Kim regime from its ability to launder money through third-country banks would be the most effective way to bring Pyongyang back to the negotiating table, Royce argues. He pointed to the Bush administration’s sanctions against Banco Delta Asia and several other financial institutions, which eventually led to negotiations with the government of Kim Jong Il.

“If we add this component, then we are back to the type of leverage we had in 2005,” Royce said. “From defectors from North Korea, we know what the consequences of that was.”

The U.S. government messaging on North Korea has not been consistent. On Monday, Trump said he’d be “honored” to meet Kim Jong Un under the right circumstances. But Vice President Pence told me last month that the goal was to persuade North Korea to abandon its nuclear and missile programs without negotiations.

Last week, after briefing Congress on the North Korean situation, Secretary of State Rex Tillerson, Defense Secretary Jim Mattis and Director of National Intelligence Dan Coats issued a joint statement saying that the objective of pressure was to persuade Kim to “return to the path of dialogue.” Adm. Harry Harris, head of U.S. Pacific Command, testified last week that the U.S. goal with Kim Jong Un is to “bring him to his senses, but not to his knees.”

What’s common to all of those messages is the acknowledgment that more pressure is needed now on North Korea and its enablers, not on U.S. allies.

On April 28, Secretary of State Rex Tillerson urged nations of the United Nations Security Council to pressure anew North Korea to "dismantle" its nuclear weapons program. (The Washington Post)