Trump wanted to improve relations with Putin, but Senate Republicans may complicate his plans.

President-elect Donald Trump’s plans to warm relations with Russia are set to be complicated by new sanctions placed on Russia’s top intelligence agencies and Obama’s decision to expel a number of Russian emissaries.

Russian President Vladimir Putin said Friday that he will not expel American diplomats, despite the Obama administration’s jettison of 35 Russians from the United States over accusations of hacking and election interference.

“While we reserve the right to respond, we will not drop to this level of irresponsible diplomacy, and we will make further steps to help resurrect Russian-American relations based on the policies that the administration of Trump will pursue,” Putin said in a statement published on the Kremlin’s website. Putin said the expulsion was a provocation but chose not to immediately retaliate, despite suggestions to do so from Russian Foreign Minister Sergei Lavrov.

U.S. intelligence agencies have concluded that one of Russia’s top intelligence agencies, the G.R.U., ordered a Kremlin-approved attack on the Democratic National Committee and other political organizations, resulting in the DNC email hacks that bolstered the Trump campaign. The Obama administration retaliated to the interference on Thursday by expelling 35 Russians, thought to be spies posing as diplomats, and sanctioning Russia’s top two intelligence agencies. Top Obama aides told the New York Times that despite the seriousness of the matter, they don’t believe Russian interference affected the election’s outcome.

This isn’t the first time Obama used sanctions as a weapon against Russia. In 2014, when Russia invaded Ukraine and annexed Crimea, the administration sanctioned dozens of Russians, including close friends of Putin. Those sanctions were much harsher than the latest round.

The sanctions also have given President-elect Donald Trump a difficult decision to make once he takes office. Trump spoke about improving the U.S. relationship with Russia in the run up to the election, and one of his top aides seems to view Putin as an ally in the fight against liberalism. He also cast doubt on claims by intelligence agencies that Russia was behind the hacking, instead suggesting during a presidential debate that it might be “somebody sitting on their bed that weighs 400 pounds.”

The new sanctions enacted by the administration will “likely will box in the Trump administration, if not legally then certainly politically, because it’s going to be hard for the administration to come in and say on day one all the reports were untrue, the FBI was wrong, the CIA was wrong,” Eric Lorber, a senior adviser at the Center on Sanctions and Illicit Finance at the Foundation for Defense of Democracies, told Bloomberg. “It will be difficult for the incoming administration to make that argument to the American people and say the sanctions should be completely done away with.”

Now, Trump will have to decide if he should repeal sanctions on Russia’s intelligence agencies. While Trump will have the executive power to do so, he would likely face strong opposition from members of his own party. Sens. John McCain (R-AZ) and Lindsay Graham (R-SC) are among the prominent Republicans advocating sanctions against the Kremlin. He may also face opposition to his Secretary of State appointment Rex Tillerson, the Exxon Mobil CEO, from figures like McCain. Tillerson defied State Department policy multiple times during Obama’s reign and opposed sanctions on Russian figures following the annexation of Crimea.

Senate Majority Leader Mitch McConnell (R-KY) also called for a strong response to Russia’s actions.

“The Russians are not our friends,” McConnell said in a statement. “Sanctions against the Russian intelligence services are a good initial step, however late in coming. As the next Congress reviews Russian actions against networks associated with the U.S. election, we must also work to ensure that any attack against the United States is met with an overwhelming response.”

The circus surrounding the issue garnered a response from Trump on Thursday.

“It’s time for our country to move on to bigger and better things,” Trump said in a statement. “Nevertheless, in the interest of our country and its great people, I will meet with leaders of the intelligence community next week in order to be updated on the facts of this situation.” He did not mention Russia.

The United States is not the only country that suspects Russian interference in a domestic election. Italy, Germany, and France all have upcoming elections and politicians there fear the viral spread of fake news and timed leaks — tactics attributed to Russia’s team of hackers.

“The goal here was to make it abundantly clear that Russia was behind the hacking attempts,” John Hughes, a vice president at Albright Stonebridge Group and a former sanctions expert at both the Treasury and State departments, told Bloomberg. “I can’t remember a time that they’ve done so much to declassify certain information and make it clear how Russia is doing this and pointing a smoking gun at the Russian intelligence services. That is pretty significant.”