Dutch Defense Minister Ruben Brekelmans said while on a surprise visit to Kyiv on Sunday that his country will invest €400 million ($440 million) in advanced drone development with Ukraine and deliver more F-16s in the coming months.

More than 2½ years since the start of the Russian full-scale invasion, Ukraine is fighting to thwart Russia's troops as they inch forward in the east and attack critical infrastructure ahead of the winter months.

"The war, of course, is intensifying every day, and Ukraine is setting up more brigades who all need support, who all need military equipment. We need to have this continuous flow of support," Brekelmans said in Kyiv.