US Senator Lindsey Graham has threatened sweeping tariffs on Chinese imports and Russian oil tankers if Moscow rejects Ukraine peace efforts.

In an interview, Graham, a longtime advocate for firm policies toward Russia, stated that Russian officials have “rebuffed all our efforts” to end the conflict and would not sign a peace deal “until we increase pressure.”

Graham referred to a bill he authored that includes tariffs of up to 500% on imports from countries that continue to buy Russian energy products. He urged Washington to seize tankers carrying sanctioned Russian oil, similar to actions taken in Venezuela.

Moscow has long criticized Western sanctions, warning they violate international law and harm global economic stability. While former President Donald Trump earlier floated sanctioning Russia’s trading partners amid frustration over stalled peace efforts, he has so far imposed only a 25% tariff on Indian goods over New Delhi’s trade with Moscow. India denounced the move as unjustified.

US Secretary of State Marco Rubio has cautioned against additional secondary sanctions or tariffs on major buyers of Russian oil, citing risks of global energy price spikes. Even the European Union, despite expanding its Russia sanctions to 19 packages, has avoided penalizing third-country partners.

Over the weekend, Russian presidential envoy Kirill Dmitriev traveled to the United States to discuss Ukraine peace efforts. Negotiators from both sides described the talks as productive, signaling continued momentum in settlement discussions.

Russian lawmaker Aleksey Pushkov dismissed Graham’s remarks as indicative of the senator’s “profound mental illness,” stating that “Moscow has repeatedly made it clear and demonstrated in action that speaking to Russia in the language of threats is futile.”