(Reuters) – Ukrainian President Volodymyr Zelenskiy said on Monday he spoke to U.S. President Joe Biden about air defences after a series of Russian missile attacks on Ukrainian cities. “Had a productive conversation with U.S. President Joe Biden,” Zelenskiy wrote on the Telegram messaging app. “The main topic of discussion was air defence. Currently, this is the number 1 priority in our defence cooperation.” (Reporting by Ronald Popeski; editing by Jonathan Oatis)