WASHINGTON — Lawmakers in Washington worked quickly Tuesday to set legislative guardrails in support of NATO as President Donald Trump, who has repeatedly bashed the alliance, arrived in Europe for a NATO summit and meeting with Russian President Vladimir Putin later in the week.

Hours after Trump landed in Brussels, the Senate passed a non-binding measure, 97-2, that expresses support for NATO, its mutual self-defense clause and calls on the administration to rush its whole-of-government strategy to counter Russia’s meddling in the U.S. and other democracies.

With the established global order on shaky footing, Trump’s weeklong trip to Europe will test already strained bonds with some of America’s closest allies, then put him face to face with the leader of the country whose electoral interference was meant to help put him in office.

Senate Armed Services Committee ranking member Sen. Jack Reed, D-R.I., proposed the measure, which is technically a motion to instruct lawmakers who will reconcile the House and Senate defense policy bills for 2019. Republican Sens. Rand Paul and Mike Lee were the only senators to vote against it.

In a Senate floor speech Tuesday, Reed callled America’s commitment to NATO “ironclad” and Trump’s meeting with Putin “ill-advised.”

“I join my colleagues this afternoon in support of the motion which sends an important message to our allies, our partners, and our adversaries that the United States is unwavering in its support of Europe free from the threat of external aggression and in support of the rules-based international order that has promoted international security for decades,” Reed said.

The Senate Foreign Relations Committee was expected Wednesday to debate a separate measure supporting NATO. One proposed amendment to it, from panel chairman Bob Corker, R-Tenn., would reaffirm support of Ukraine’s sovereignty and condemn “Russia’s illegal invasion and attempted annexation of Crimea.” A second proposed amendment from Sen. Robert Menendez, the panel’s ranking member, would reaffirm support for U.S. sanctions against Russia.

Trump’s wavering on NATO has led allies to question America’s trustworthiness, Menendez, D-N.J., said in a blistering floor speech.

“In the absence of U.S. presidential leadership, I want to make clear to our allies abroad, as well as our adversaries in the Kremlin, as to where members in the United States Senate stand,” said Menendez, adding that the chamber stands for the rule of law, an international order based on democratic values and with its allies.

“President Trump’s slap-dash approach to foreign policy, borne out of heated campaign rallies, instead of thoughtful Cabinet meetings, has real implications for our national security,” Menendez said. “Such reckless behavior by President Trump has weakened the United States on the global stage and created a more dangerous world for our citizens and our troops serving abroad.”

Menendez ripped Trump for saying his meeting with Putin would be the easiest of his four-country trip, as a sign Trump “would rather deal with an autocrat than negotiate with democratically elected leaders.”

“Let’s be clear: Meeting with a thug intent on undermining American democratic values should not be easy and it should not be chummy,” he said.

Menendez’s pursuit for a vote on Russia sanctions follows Sen. Ron Johnson, R-Wis., saying — after a trip to Russia last week — the Senate may have gone too far with mandatory sanctions against a host of Russian entities, leaving Trump with too little negotiating room on other matters.

Johnson, chairs the Foreign Relations subcommittee for Europe, told the Washington Examiner, the sanctions, “don’t seem to be having a real horrible economic effect, not in Moscow anyway.”

Speaking with reporters and on Twitter from his flight, Trump repeated his call for NATO countries to fulfill their goal of spending 2 percent of their gross domestic product on defense by 2024. The summit is expected to be marked by disagreements over trade and military spending.

After the NATO summit in Brussels, Trump will travel to the UK and then Helsinki to meet with Putin. The meeting will be closely watched to see whether Trump will rebuke or embrace Putin, who has repeatedly denied the allegations of election meddling in spite of evidence to the contrary.

Republicans, in their support for Trump, have put the accent on his burden-sharing message — and several offered a resolution of their own that reinforces the need for greater defense spending in the alliance, as well as support for NATO.

“Only fair and equitable burden-sharing will make ‘peace through strength’ a NATO reality in the face of growing threats, including Russian aggression, terrorism and cybersecurity,” said Sen. Jim Inhofe, a senior member of the Senate Armed Services Committee. “President Trump is right to strongly encourage all of our NATO allies to meet their commitment to defense spending under the collective security obligations.”

Outside of the Senate chamber, lawmakers expressed fears over both tone and substance of Trump’s talks at the NATO and Putin summits.

On the heels of leading a Republican delegation to Russia last week, Senate Appropriations Committee Chairman Richard Shelby cautioned Trump to be well-prepared, especially after the summit with North Korean leader Kim Jong Un produced, “a lot of optics and not a lot of substance yet.”

“My advice to the president, if he wanted any, would be: Careful, you’re dealing with a tough man, a smart man, and he probably wants to get something and give nothing in return,” Shelby, R-Ala., said of Putin.

Shelby also expressed some openness to easing sanctions if the deal was right.

“Would there be anything the Russians would concede,” he said. “If they want something, we ought to get something. They ought to earn their way.”

Senior administration officials said discussions of withdrawing U.S. troops from Germany will not be included in next week’s NATO summit, despite reports that Trump has considered the move.

“I think the president should listen to his security council and his secretary of defense on anything of substance dealing with the U.S. military posture,” Shelby said of the issue. “We’ve got to be careful. We’ve got to be strong. Concede nothing.”

Sen. Jeff Flake, a Republican critic of Trump’s who recently returned from a European trip, said the president ought to clearly stipulate Russia’s annexation of Crimea was illegal, that Russia ought to vacate Ukraine and that Russia interfered in U.S. elections.

“I know that our NATO allies are afraid of what the president might promise in terms of exercises, in terms of troops, location of troops, NATO expansion — whether it can take place,” said Flake, R-Ariz., adding that he was concerned, too.

Along similar lines, Senate NATO Observer Group Co-Chair Sen. Jeanne Shaheen, D-N.H., said Trump ought not to give Crimea to Russia. Halting U.S. involvement in joint exercises would be “disastrous,” she added.

“It undermines NATO, and NATO is crucial to our security,” she said. “The president doesn’t seem to understand that.”

Trump may not have the ability on a variety of issues to act unilaterally to make concessions on Crimea, sanctions or NATO’s structure, but even promising to do so would be troubling, said Sen. Chris Coons, D-Del. Coons, a Senate Foreign Relations Committee member, recently traveled to Sweden, Finland, Latvia and Denmark.

“Even rhetorically conceding ground on Crimea, on eastern Ukraine, on sanctions, I think undermines our close alliance with our European partners who have continued to extend tough sanctions on Russia for their ongoing intervention in Ukraine,” Coons said.