President Biden is facing mounting pressure to lift the ban on Ukraine using U.S. weapons to strike deep inside Russia and appeared to admit on Tuesday that his administration is moving in that direction. 

"We’re working that out right now," he said when asked by reporters whether he would allow Ukraine to use the long-range Army Tactical Missile System, or ATACMS, to target sites inside Russia.

Support for lifting the ban has come from all sides.

A group of high-level House Republicans wrote to the president this week arguing that such restrictions "have hampered Ukraine’s ability to defeat Russia’s war of aggression and have given the Kremlin’s forces a sanctuary from which it can attack Ukraine with impunity."

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The House GOP letter was signed by House Foreign Affairs Committee Chair Michael McCaul, House Intelligence Committee Chair Michael Turner, House Armed Services Committee Chair Mike Rogers and other committee leaders.

Ukraine children's hospital

People stand near the building of one of the largest children's hospitals in Ukraine that was partially destroyed by a Russian missile strike on July 8, 2024, in Kyiv, Ukraine. (Oleksandr Gusev/Global Images Ukraine via Getty Images)

It critiques the Biden administration but contrasts statements from top Republicans like Donald Trump, who have suggested he could bring a diplomatic end to the war. 

On Wednesday, a group of liberal and progressive former high-level national security officials authored a letter calling on the U.S. and U.K. to allow unrestricted use of their weapons to strike Russian territory. 

A bipartisan group of House and Senate members sent another letter arguing that with the ban, Russia "is far too comfortable in its ability to focus on its offensive operations rather than defending itself."

"Easing the restrictions on Western weapons will not cause Moscow to escalate," they wrote. "We urge you to listen to your partners in Kyiv this week and allow Ukraine to strike all legitimate targets in Russia with the weapons the U.S. and U.K. have provided. Let Ukraine defend itself."

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Ukrainian President Volodymyr Zelensky has implored U.S. officials to lift the ban they placed to avoid escalation of U.S. involvement in the war. Washington in recent months has partially done so, allowing Ukraine to use U.S. weapons for defensive strikes "within sovereign Ukraine territory."

U.S. Secretary of State Antony Blinken traveled to Kyiv on Wednesday with British Foreign Secretary David Lammy and were expected to gather information on how such long-range strikes would factor into Ukraine’s broader battlefield strategy. The U.K. is also considering whether to allow Ukraine to strike deeper inside Russia with its own long-range system, the Storm Shadow.

Asked about the "green light" to target inside Russia on Thursday, Blinken did not indicate any change in policy but restated a desire to keep adapting to Russia’s aggression.

Blinken said he expects Biden and U.K. Prime Minister Keir Starmer to discuss the topic when they meet Friday in Washington.

Ukrainian soldiers Kursk invasion

(ROMAN PILIPEY/AFP via Getty Images/File)

Ukraine military

Ukrainian servicemen of the 21st Separate Mechanized Brigade operate a Leopard 2A6 tank during a military exercise. (REUTERS/Valentyn Ogirenko/File)

Last week, Defense Secretary Lloyd Austin pushed back on the notion that lifting restrictions and allowing Ukraine to hit deeper into Russia would change the tides of the war. 

"There’s no one capability that will, in and of itself, be decisive in this campaign."

"There are a lot of targets in Russia, a big country, obviously," Austin said at a meeting of the Ukraine Defense Contact Group in Germany on Friday. "And there’s a lot of capability that Ukraine has in terms of (unmanned aerial vehicles) and other things to address those targets."

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The debate about whether to remove the restrictions comes amid the worrying beginning of transfers of Iranian ballistic missiles to Russia.

Some worry the U.S. has a limited number of ATACMS to offer Ukraine without affecting U.S. readiness and that using the weapons to strike deep into Russia could deplete their supply for other parts of the military campaign, like inside Crimea. But advocates of lifting the ban argue Ukraine is already using ATACMS on territory that Russia sees as its own in Crimea.