Nearly a month after President Donald Trump signed a sweeping Russian sanctions bill named after Lindsey Graham, bipartisan leadership in the Senate is urging the administration to act to help Ukraine.

LISA MASCARO WASHINGTON — Nearly a month after President Donald Trump signed a sweeping Russian sanctions bill named after Lindsey Graham into law, bipartisan leadership in the Senate is urging the administration to clamp down more quickly on the flow of financial resources fueling the war against Ukraine In a letter to Treasury Secretary Scott Bessent Secretary of State Marco Rubio the senators said the most urgent priority for the U.S. must be to tackle the “shadow fleet” of tankers that Moscow is using to transport oil and bypass America’s sanctions. They also pushed for a halt of Russia’s emerging satellite system that Ukraine has warned could prove devastating with real-time bombing attacks this winter.

“Every day that passes without maximum economic pressure allows Moscow to sustain this military escalation,” wrote Sen. Jeanne Shaheen of New Hampshire, the top Democrat on the Senate Foreign Relations Committee, and Republican Sen. Roger Wicker of Mississippi, chairman of the Senate Armed Services Committee.

The senators note that the bulk of the law’s provisions go into effect Oct. 18, the end of the administration’s 30-day review period. The Trump administration has remained mostly quiet since the passage of the bill with large bipartisan majorities in the House and Senate after Graham’s sudden death, with lawmakers urged ahead by Ukraine President Volodymyr Zelenskyy.

Trump has been expected to speak with Russian President Vladimir Putin, whose birthday is Wednesday, to discuss a possible case of plague at a Siberian research institute.

Congress backed Ukraine with the Russian sanctions package sanctions package had been a year in the making but was suddenly rushed to passage after Graham, the long-serving South Carolina senator, died in July of a likely torn aorta after a whirlwind trip to a NATO summit in Turkey and a stopover in Kyiv.

Senators had been negotiating a bipartisan bill that could win robust support but it was only when Graham received the nod of approval from Trump in the days around the senator’s overseas trip that it gained momentum.

Zelenskyy had also been pushing the U.S. to act, and he arrived in the Senate after a visit at the White House late in the evening before a key vote that advanced the package. The House gave final approval to the bill, sending it to Trump’s desk, but Democrats in both chambers warned that they doubted the president would use the vast tools available to slap back at Russia.

In the month since, momentum appears to have stalled without public steps from the administration toward the law’s implementation.

Trump’s next moves against Russia are uncertain With the bipartisan push, Shaheen and Wicker in their letter sent late Tuesday are urging the administration to take several specific steps to impose the sanctions regime. Many of the steps are aligned with goals pushed by the Ukrainians.

The senators, who were both key to the bill’s passage, said it’s most crucial for the U.S. to focus on the several hundred rogue tankers that are able to “transport Russian oil with impunity and thereby provide the Kremlin a financial lifeline.”

It’s also, imperative, they wrote, “that the administration paralyze the global financial networks that allow Russia to evade our sanctions.”They said the Kremlin continues to “move billions of dollars through networks that shield it from scrutiny.”They urged the administration to focus specifically on overseas bank branches, including in Shanghai, and “a growing network of Kyrgyz financial institutions” they said serve as clearinghouses for sanctioned capital.

“Foreign banks must be forced to make a choice.” the senators wrote. “They can either do business with the United States or finance Russia’s war. They cannot do both.”They said the Trump administration should work to undermine Russia’s “weaponization of space” with its emerging low Earth orbit system. Ukraine has warned that such a satellite system would prove deadly in the coming winter as Russia prepares its attacks.

The senators also noted that the sanctions law bans all new U.S. investment in Russia and handling of sovereign debt. They said it’s imperative that the Treasury Department “issue clear regulatory guidance ahead of the October deadline to ensure American financial institutions completely sever these capital pipelines.”

Additionally, the senators said the U.S. must stop the flow of dual-use technologies and electronics for Russia’s frontline operations, and use the sanctions tools available to “penalize entities feeding Russia’s military-industrial complex.”