(CNN) The Biden administration has signaled to European allies in recent weeks that the US would allow them to export F-16 fighter jets to Ukraine, sources familiar with the discussions said, as the White House comes under increasing pressure from members of Congress and allies to help Ukraine procure the planes amid intensifying Russian aerial attacks.
Administration officials are not aware, however, of any formal requests by any allies to export F-16s, and State Department officials who would normally be tasked with the paperwork to approve such third-party transfers have not been told to get to work, officials said.
A handful of European countries have a supply of the US-made F-16s, including the Netherlands, which has signaled a willingness to export some of them to Ukraine. But the US would have to approve that third party transfer because of the jets’ sensitive US technology.
While the US remains reluctant to send any of its own F-16s to Kyiv, US officials told CNN that the administration is prepared to approve the export of the jets to Ukraine if that is what allies decide to do with their supply.
National Security Council coordinator for strategic communications John Kirby declined to comment specifically on the possibility of the US sending F-16 fighter jets to Ukraine, but said broadly that the US has been forward-looking about “future capabilities” and needs. F-16s are “not on the agenda” at the G7, he said, though the aircraft could certainly come up on the sidelines of the summit.
US lawmakers and congressional staffers have joined in the F-16 lobbying campaign, urging the administration to provide the jets so that Ukraine can establish control over its skies.
“As a bipartisan group of lawmakers, we view the transfer of F-16 fighter aircraft to Ukraine as essential for providing Kyiv with the air support capability required to fully defend their nation against Russia’s unprovoked, illegal, and brutal invasion, and to make the territorial gains necessary to reclaim their country,” a group of Republican and Democratic lawmakers wrote in a letter to President Joe Biden on Wednesday that was obtained by CNN.
The issue is expected to be a subject of debate at the next NATO summit in Vilnius, Lithuania, in July, officials said.
Another open question is where Ukrainian pilots would train on these F-16s. A spokesperson for UK Prime Minister Rishi Sunak said earlier this week that the UK and the Netherlands were looking to form an “international coalition” not only to procure the jets for Ukraine but also to train Ukrainian pilots on the 4th generation fighters, which are more advanced than the Ukrainian fighter fleet.
In March, the US hosted two Ukrainian pilots at a military base in Tucson, Arizona to evaluate their skills using flight simulators and to assess how much time they would need to learn to fly various US military aircraft, including F-16s. But US has no plans as of now to expand that training, a defense official told CNN, despite Congress setting aside money in the 2023 budget for such training.
US allies with F-16s could conduct training for Ukrainian fighter pilots, or the aircraft’s manufacturer, Lockheed Martin, could carry out training as a private contractor. But the defense official said such an arrangement would likely need some level of US participation, even if it doesn’t require an official US sign off like the transfer of US weaponry overseas.
Ukrainians upping their lobbying campaign
Top Ukrainian officials have escalated their public lobbying campaign for US-made F-16s in recent months, arguing they need them urgently to defend against Russian missile and drone attacks.
Russia launched an “unprecedented” series of missile attacks on Kyiv on Thursday morning, a Ukrainian official said, just days after Russia launched a barrage of six hypersonic missiles near the capital aimed at destroying Ukraine’s Patriot air defense systems.
“A series of air attacks on Kyiv, unprecedented in their power, intensity and variety, continues,” said Serhii Popko, head of Kyiv’s civil and military administration.
Without the jets, Ukraine is having to improvise, officials say. Defense officials and congressional staffers told CNN that Ukrainian troops have in recent weeks used the US-made Patriot air defense system to shoot down at least one faraway Russian fighter jet. The Russian jets have largely been staying behind Russian defensive lines, making them difficult for Ukraine to target with shorter-range systems like NASAMs.
The Russian planes the Patriot targeted were on a bombing run to fire missiles against Ukrainian targets, US officials said, which Russia has been doing throughout the past year to maximize civilian casualties.
The officials said the Ukrainians were responsible for making their own firing decisions once the west provided the Patriot systems, noting it is up to the Ukrainians when and how to engage the Patriots to protect their people.
Sophisticated fighter jets would make it easier for Ukraine to target the Russian planes, some congressional staffers argue, without having to expend expensive Patriot munitions that were made to intercept ballistic missiles.
Some US officials are skeptical of that argument, however, and note that Russia has extensive anti-aircraft systems that could easily shoot down the F-16s. Ukraine has not been conducting many air missions with the fighter planes it already has for precisely that reason, officials have said.
Still, there is a belief in Kyiv that with enough public pressure, the Ukrainians can eventually secure weapons systems that were once deemed a red line by the west. HIMARS, battle tanks, and the Patriot battery were all once considered off-limits — all are now either in country or heading there soon.
While the UK does not have any F-16s of its own, the British government appears to have done a U-turn on the issue over the last several months. In January, a British government spokesperson told reporters that the UK believes that the jets “are extremely sophisticated and take months to learn how to fly. Given that, we believe it is not practical to send those jets into Ukraine.”
On Monday, Ukrainian President Volodymyr Zelensky said that Kyiv and London were “actively moving forward” on a plan to procure them.
“We need F-16s,” Andriy Yermak, head of the office of the Ukrainian president. “And I am grateful to our allies for their decision to work in this direction, including training our pilots.”
CNN’s Zachary Cohen and Jennifer Hansler contributed reporting.