A top Biden administration defense official on Tuesday said it is not clear how many more rounds of American taxpayer aid will be needed to sustain Ukraine in its war with Russia.

Dr. Colin Kahl, the No. 3 official at the Pentagon was asked during a hearing by Rep. Ro Khanna (D-CA) how many more rounds of aid the Biden administration expects to request for Ukraine.

Khanna asked: “Just in terms of the American public, how many more times do you think Congress needs to provide aid?”

Kahl responded: “You know, it’s difficult, and it’s difficult because we don’t know the course and trajectory of the conflict. The conflict could end six months from now, it could end two years from now, or three years from now.”

“I think the president has said the United States will continue to support Ukraine for as long as it takes,” he added. “I would hope that Congress would continue to be supportive.”

File/U.S. National Security Adviser, Colin Kahl, delivers a speech during a panel discussion as part of the U.S.-Islamic World Forum on June 1, 2015 in the Qatari capital Doha. (/AFP via Getty Images)

Last week, President Joe Biden made a surprise visit to Ukraine to reaffirm U.S. commitment to Ukraine, followed by a visit by Treasury Secretary Janet Yellen. After Biden’s visit, the Pentagon announced $2.5 billion more in military aid, and Yellen announced a transfer of $1.25 billion in economic aid out of a $10 billion fund.

There is rising American public opposition to supporting Ukraine “for as long as it takes.”

A poll published by NBC News in January said 46% oppose Congress approving more aid for Ukraine, while 49% approve.

Congress has already allocated $113 billion for the year-old conflict, which has no end in sight.

Kahl said that the Pentagon has spent nearly $32 billion so far, and has roughly $12 billion more for the rest of the fiscal year. The rest of the aid is going towards Ukraine’s government and economy.

The billions of dollars of aid to Ukraine has come amid American public anxiety over high inflation for basic consumer goods, looming social security insolvency, a debate over student loan forgiveness, and a string of high-profile train derailments.

There is also growing concern that aid to Ukraine will leave U.S. military arsenals dry for helping Taiwan in a potential conflict with China.

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