President Biden defended his decision on Friday to provide Ukraine with cluster munitions, which are outlawed by many of America’s closest allies, saying it was a difficult decision but “the Ukrainians are running out of ammunition” in the fight against Russian forces.
For months, Mr. Biden had wrestled with the decision to supply the weapons, which scatter tiny, deadly bomblets across the battlefield. They have been known to cause grievous injuries months or even years after the fighting ends, often among children who pick up duds that did not explode when initially dropped.
Ultimately, the president determined that depriving Ukraine of the weapons would amount to leaving it defenseless against Russia. He said it was a temporary move to hold Ukraine over until the production of conventional artillery rounds could be ramped up.
“It was a very difficult decision on my part — and by the way, I discussed this with our allies, I discussed this with our friends up on the Hill,” Mr. Biden said in an interview with CNN. “The Ukrainians are running out of ammunition.”
“And so, what I finally did, I took the recommendation of the Defense Department to — not permanently — but to allow for this transition period,” he added.
The decision was a break with several of America’s closest allies and led to criticism from Democrats, who expressed concerns that the weapons risked the moral standing of the United States. The move could also complicate efforts to demonstrate unity when Mr. Biden attends a NATO summit next week in Lithuania.
Jens Stoltenberg, the secretary general of NATO, dodged a question on whether he believed it was wise for the United States to provide the weapons to Ukraine.
“It is for individual allies to make decisions on the delivery of weapons and military supplies to Ukraine,” Mr. Stoltenberg told journalists at NATO’s headquarters in Brussels. “So this will be for governments to decide — not for NATO as an alliance.”
Russia, U.S. officials have noted, has been using its cluster munitions in Ukraine for much of the war. The Ukrainians have also used them, and President Volodymyr Zelensky has been pressing Mr. Biden to supply him with more in order to flush out the Russians who are dug into trenches and blocking Ukraine’s counteroffensive.
Jake Sullivan, the president’s national security adviser, told reporters at the White House on Friday that Ukraine had made a direct appeal for the weapons several weeks ago.
“Ukraine would not be using these munitions in some foreign land,” Mr. Sullivan said. “This is their country they’re defending. These are their citizens they’re protecting, and they are motivated to use any weapon system they have in a way that minimizes risks to those citizens.”
Mr. Sullivan said the Ukrainians promised to use the weapons in a way that would avoid civilians, but he said there were no guarantees.
“The battlefield is shifting at all times,” he said.
Many allies of the United States that support Ukraine have drawn a line at providing cluster munitions. Germany and France are among more than 100 nations that have signed a treaty prohibiting the weapons; the United States, Russia and Ukraine have not.
The United States never joined the pact because officials believed that cluster munitions could be useful on the battlefield. The United States used cluster munitions during the war in Iraq, according to the Cluster Munition Coalition, a campaign that calls for an end to the use of the weapons. Saudi Arabia used American-made cluster munitions during the war in Yemen until the United States stopped the transfer amid concerns that civilians would be harmed.
American allies reacted with caution on Friday to Mr. Biden’s decision.
While Germany and France did not criticize the United States or oppose the move, the countries said they would not follow suit.
The Pentagon said on Friday that the administration’s decision would quickly provide hundreds of thousands of cluster munitions to Ukraine at a pivotal time when Ukraine’s monthlong offensive is flagging.
In order to approve the weapons for Ukraine, Mr. Biden had to waive a law that prohibits the transfer of such weapons that have a failure rate of more than 1 percent.
In a briefing to reporters at the Pentagon, Colin H. Kahl, the under secretary of defense for policy, said the munitions being sent to Ukraine had a low dud rate.
“These munitions are pretty close to 1 percent, but they’re not at the 1 percent level,” he said. “But the president does have the authority to waive that requirement on national security grounds, and that’s what he has done in this instance.”
Recognizing the moral and diplomatic sensitivities of sending Ukraine weapons that are banned by most of Washington’s allies, Mr. Kahl said the Russians were already indiscriminately using cluster munitions with failure rates of up to 40 percent on the battlefield, posing huge risks to civilians. Ukraine wants to use the same weapons to defend its own territory, and understands the risks of doing so, he said.
Mr. Kahl also said that the United States would work with Ukraine to minimize the risks associated with cluster munitions. Specifically, the Ukrainian government has said that it will not use the rounds in densely populated urban areas, and that using the rounds would make demining efforts easier after the conflict.
“There would be a careful accounting of where they use these weapons,” Mr. Kahl said.
Since World War II, cluster munitions have killed an estimated 56,500 to 86,500 civilians. They have also killed and wounded scores of American service members. Additional civilians, including children in Syria, Yemen, Afghanistan, Lebanon, the Balkans and Laos, continue to suffer from incidents involving remnants of cluster munitions.
On Friday, Ukraine’s defense minister, Oleksii Reznikov, said the decision would “significantly help us to de-occupy our territories while saving the lives of the Ukrainian soldiers.”
On Capitol Hill, several Democrats criticized the decision, arguing that the weapons could cause indiscriminate harm to civilians long after the fighting ends.
“I continue to strongly support helping Ukraine stand up to Russia’s brutal war of aggression,” Representative Jim McGovern, Democrat of Massachusetts and ranking member of the House Rules Committee, said in a statement. “But cluster munitions won’t help.”
The few Republicans who spoke about Mr. Biden’s decision on Friday, however, praised him for taking what they said was a necessary step.
“For Ukrainian forces to defeat Putin’s invasion, Ukraine needs at least equal access to the weapons Russia already uses against them, like cluster munitions,” Senator Tom Cotton, Republican of Arkansas, said in a statement. “Providing this new capability is the right decision — even if it took too long — and is one I’ve long supported.”
Lara Jakes, Karoun Demirjian, Zolan Kanno-Youngs and John Ismay contributed reporting.