Russia attacked Denmark and the Netherlands’ plan to deliver F-16 fighter jets to Ukraine on Monday, saying the move will worsen the war.

Denmark and the Netherlands confirmed on Sunday that they will equip Ukraine with F-16s, with the first six scheduled to arrive around the New Year.

“The fact that Denmark has now decided to donate 19 F-16 aircraft to Ukraine leads to an escalation of the conflict,” said Russian envoy Vladimir Barbin, according to the Ritzau news agency.

“By hiding behind a premise that Ukraine itself must determine the conditions for peace, Denmark seeks with its actions and words to leave Ukraine with no other choice but to continue the military confrontation with Russia,” he said.

Danish Defence Minister Jakob Ellemann-Jensen said Ukraine may only use the donated F-16s within its own territory.

“We donate weapons under the condition that they are used to drive the enemy out of the territory of Ukraine. And no further than that,” Ellemann-Jensen said on Monday.

“Those are the conditions, whether it’s tanks, fighter planes or something else,” he said.

Denmark will deliver 19 jets in total. The Netherlands has 42 F-16s available in all but has yet to decide whether all of them will be donated.

Ukrainian President Volodomyr Zelenskiy said on Sunday the planes would strengthen Ukraine’s air defences and help its counter-offensive against Russian forces.