President Donald Trump said Friday the United States must be “very careful” about giving Ukraine a licence to produce Patriot air defence missiles, which Kyiv says it needs to defend against Russian attacks.

“These weapons are incredible. We have to be very careful about letting somebody build them,” Trump said at the Camp David presidential retreat in response to a question about allowing Ukraine to produce the missiles.

Ukraine’s President Volodymyr Zelensky met with Trump for just over an hour at the White House earlier this week for talks that came as Kyiv and Moscow intensify long-range strikes after US-led diplomatic efforts to end the war stalled.

Zelensky said following the meeting that Trump had agreed to license Patriot production to Ukraine, but the US president only said that “many things were discussed” and “the meeting went very well!”

Relations between Zelensky and Trump have warmed since the start of the US president’s second term, and Trump suggested earlier this month that Ukrainian strikes inside Russia could help end the war.

Last month was the deadliest for Ukraine civilians since April 2022, according to the United Nations, as Russia increased its use of difficult-to-intercept ballistic missiles.