President Donald Trump campaigned on easing tensions with Russia, arguing that it would be in America’s best interest to try warming relations with Vladimir Putin.

But Congress is looking more and more likely to stand in his way. In a 98-2 vote on Thursday, the Senate overwhelmingly approved a series of sanctions to punish Russia for meddling in the 2016 US presidential election. The bill also included a suite of sanctions against Iran.

If passed, the new Russia provisions would make it more difficult for Trump to relax sanctions against the country. According to a press release, the sanctions bill would also:

— Impose new sanctions on: corrupt Russian actors; those seeking to evade sanctions; those involved in serious human rights abuses; those supplying weapons to the Assad regime; those conducting malicious cyber activity on behalf of the Russian government; those involved in corrupt privatization of state-owned assets; and those doing business with the Russian intelligence and defense sectors. — Allow broad new sanctions on key sectors of Russia’s economy, including mining, metals, shipping and railways. — Authorize robust assistance to strengthen democratic institutions and counter disinformation across Central and Eastern European countries that are vulnerable to Russian aggression and interference. — Require a study on the flow of illicit finance involving Russia and a formal assessment of U.S. economic exposure to Russian state-owned entities.

Senate Minority Leader Chuck Schumer (D-NY) told CNN that "we moved to make the Congress, not the President, the final arbiter of sanctions relief when necessary.” Indeed, the bill requires a congressional review if the president attempts to ease or end sanctions against Moscow, according to the Associated Press.

Despite overwhelming bipartisan support, Sen. Bernie Sanders (I-VT) voted against the bill. In a statement, Sanders said that he opposed the bill not because of the new Russia sanctions, which he supports, but because of the additional sanctions against Iran that were also part of the bill. The libertarian-minded Sen. Rand Paul (R-KY) was the only other “no” vote against the bill.

It’s important to note that the measure hasn’t been signed into law. From the Senate, the bill still has to be approved by the House and then by President Trump to become law.

Senators are optimistic Trump won’t veto them. "I would be very, very surprised if the president vetoes this bill. Now, he's surprised me on a lot of things," Sen. Ben Cardin, the ranking Democrat on the Senate Foreign Relations Committee, told CNN. "I find as we get to the finish line on these bills, every administration generally joins us … so I think we'll have the support of the administration. I'm confident about that."

Democrats have long feared that Trump would respond to Russian interference in the election by turning around and helping Putin. But for now, at least, Senate Republicans appear willing to tie his hands before he can reach out to Russia.