Ukraine is scrambling to protect its skies after Russia intensified aerial attacks, launching hundreds of drones and dozens of missiles almost every day, killing civilians and damaging houses and infrastructure.

On Tuesday, a Russian drone and missile barrage on Ukraine's Dnipropetrovsk region killed 21 and wounded over 300, including 10 children.

"We discussed the protection of our people with the President -- first and foremost, the purchase of American air-defence systems," Zelensky said on social media.

He added that Kyiv was "ready to buy this equipment and support American weapons manufacturers" and that "Europe can help."

When asked if he would supply Ukraine with the Patriot missiles, one of the most advanced air defence systems in the world, Trump vaguely promised "to see if we can make some available", adding that Washington was also supplying Israel with them.

The two leaders have also discussed a potential joint drone production, Zelensky said, describing the 50-minute exchange with Trump as "good" and "substantive".

"Couldn't have been nicer," Trump said, after the closely watched meeting held behind closed doors.