Britain's defense ministry says Ukrainian agricultural exports through Black Sea ports rose to the highest in December since the start of Russia's invasion two years ago.

Shipments through the key ports had been restricted by threats of Russian attacks, crimping deliveries of wheat from one of the world's biggest exporters of grain.

The ministry said on Monday that Ukraine has been able to raise the shipments by using missile defenses and other tactics to thwart Russia's Black Sea Fleet.

It said "The health of this export route is vital in the long term: both for Ukraine's export revenue; and as a symbol that both sides are willing to suspend attacks on civilian shipping, paving the way to diminished risk and greater trade for all in the Black Sea."

On Tuesday, Russia launched missile attacks against the capital Kyiv and the eastern region of Kharkiv. Ukrainian interior minister Ihor Klymenko said at least five people were killed.

Kyiv Mayor Vitali Klitschko said 20 people including children were injured, and that houses and buildings were damaged.