WASHINGTON, Dec 18 - An aid package scheduled for Ukraine later this month will be the final one unless Congress approves additional help, the White House warned Monday, CNN reported.

While aid provided to Ukraine thus far has been essential in resisting Russia’s invasion of Ukraine, the country “still needs our help,” National Security Council spokesman John Kirby told reporters Monday.

He pointed toward a letter to Congress from the comptroller of the Department of Defense, Mike McCord, warning the department had fully allocated all remaining funding under the department’s replenishment authority earmarked for Ukraine.

“We are still planning one more aid package to Ukraine later this month. However, when that one’s done, as the comptroller Mr. McCord made clear in his note to Congress today, we will have no more replenishment authority available to us, and we’re going to need Congress to act without delay, as we have been saying,” Kirby said.

In that letter, a copy of which was obtained by CNN, McCord wrote the department will be transferring “$1,071.117 million” to its accounts to replace its stockpiles and reimburse for “defense services” provide to Ukraine. But “once these funds are obligated, the Department will have exhausted the funding available to us for security assistance to Ukraine,” McCord wrote.

“It is essential that Congress act without delay on the Administration’s pending supplemental request,” McCord said. “Doing so is in our clear national interest, and our assistance is vitally needed so Ukraine can continue its fight for freedom and to ensure Russia continues to fail in Ukraine.’

A package first introduced in October that would have provided billions of dollars in additional Ukraine funding, along with defense funding for Israel and Taiwan, has been logjammed in Congress as Republicans have demanded concessions from the Biden administration on immigration policy and border security.

Biden has said he is willing to compromise with Republicans, but a deal remains unlikely before the end of the year, even after Ukraine President Volodymyr Zelensky met with congressional leaders last week in an effort to make his case directly to lawmakers.

Over the weekend, senior White House officials, including White House chief of staff Jeff Zients, called Republican and Democratic lawmakers to try to reach a consensus on border policy changes, two sources familiar with the discussions told CNN. Homeland Security Secretary Alejandro Mayorkas was on Capitol Hill on Sunday to meet with Senate negotiators.

But, in a sign of the challenges negotiators face in trying to get an immigration deal that can pass the Senate this week, 15 GOP senators, including GOP Sen. Lindsey Graham of South Carolina – who told NBC over the weekend negotiations for a deal will likely stretch into next year – are demanding a special conference meeting in January to discuss the negotiations.

Senate Majority Leader Chuck Schumer has insisted the chamber will hold a vote on the legislation this week – but Lankford noted senators still do not have legislative text.

Congress has so far approved $113 billion in security, economic and humanitarian aid to Ukraine since Russia’s invasion of the country began in February 2022, including $46.6 billion in direct military aid. The US provides more aid to Ukraine than any other country. (cnn/ez)