Russia-Ukraine war live updates: Russian drone attack kills rescue workers in Kharkiv; Russia says NATO dialog at 'zero' but does not seek conflict

This is CNBC's live blog tracking developments on the war in Ukraine.

Russian drone strikes on Kharkiv early Friday morning killed at least four people, including three rescue workers, and injured 12 more, according to Ukrainian officials.

In a post on the Telegram messaging app, Kharkiv Mayor Igor Terekhov said Iranian-made shahed drones struck a 14-story residential apartment block, destroying several floors and resulting in a death and multiple casualties.

A repeat attack on a separate area of Ukraine's second-largest city killed three rescue workers who had arrived on the scene after the first strike, he added.

As NATO foreign ministers gather in Brussels to mark the defense alliance's 75th anniversary, Russian Deputy Foreign Minister Alexander Grushko told state news agency RIA that dialog with Moscow had been reduced to a "critical zero" by Washington and Brussels.

Grushko reportedly said relations were "predictably and deliberately" deteriorating, but that Russia has no intention of entering into open conflict with any NATO member.

As NATO foreign ministers gather in Brussels to mark the defense alliance's 75th anniversary, Russian Deputy Foreign Minister Alexander Grushko told state news agency RIA that dialog with Moscow had been reduced to a "critical zero" by Washington and Brussels.

Grushko reportedly said relations were "predictably and deliberately" deteriorating, but that Russia has no intention of entering into open conflict with any NATO member.

— Elliot Smith

Russian drone strikes on Kharkiv early Friday morning killed four people, including three rescue workers, and injured 12 more, according to Ukrainian officials.

In a post on the Telegram messaging app, Kharkiv Mayor Igor Terekhov said