Ukrainian President Volodymyr Zelensky has asked US Secretary of State Antony Blinken for Patriot air defence systems for the city of Kharkiv, which is routinely threatened by Russian missiles. Two of these systems are necessary to protect Ukraine’s second biggest city and its surrounding area, which borders Russia, Zelensky said in Kiev during Blinken’s surprise visit. US assistance for the campaign against the Russians was of crucial importance and air defence was the “biggest deficit,” Zelensky said. According to Ukrainian media reports, Blinken promised Ukraine weapons aid that could chang…