NATO Secretary-General Jens Stoltenberg argued that Ukraine should be able to use American weapons to strike inside Russian territory, in an apparent break with the Biden administration.

"I think the time has come for allies to consider whether they should lift some of the restrictions they put on the use of weapons they have donated to Ukraine because, especially now when a lot of the fighting is going on in Kharkiv, close to the border," Stoltenberg said in an interview with the Economist over the weekend. "To deny Ukraine the possibility of using these weapons against legitimate military targets on Russian territory makes it very hard for them to defend themselves."

While the NATO boss did not mention the U.S. or the Biden administration by name, the comments come as the U.S. has continued to ban Ukraine from using American weapons to target Russian territory.

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Ukrainian President Volodymyr Zelenskyy has urged the U.S. to lift the restrictions, calls that have begun to gain favor among some lawmakers on the Hill. Last week, a bipartisan group of lawmakers led by House Permanent Select Committee on Intelligence Chairman Michael Turner, R-Ohio, penned a letter to the Defense Department asking that the restrictions on U.S. weapons use be lifted.

"Ukrainians have been unable to defend themselves due to the administration's current policy," the letter read.

According to an Institute for the Study of War report, Russia has continued to amass equipment and men at the Ukrainian border for its planned Kharkiv offensive. The bulk of that equipment has remained in reserve on the Russian side of the border, the report noted, far enough away to be out of the reach of much of Ukraine’s arsenal.

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That could change if Ukraine was able to use HIMARS rocket and ATACMS missile weapons systems provided to the country by the U.S., which the report notes would likely be able to reach the Russian targets.

The recent calls to change that policy have also gained the support of House Speaker Mike Johnson, R-La., who said in an interview with Voice of America last week that the U.S. should not "micromanage" Ukraine’s war effort.

"I think we need to allow Ukraine to prosecute the war the way they see fit," Johnson said. "They need to be able to fight back."

The White House did not immediately respond to a Fox News Digital request for comment.