KYIV (Reuters) -The Ukrainian capital Kyiv and four regions may have to cut electricity supplies for longer than planned after Russian strikes overnight targeting energy infrastructure, a senior official said on Thursday. Kyrylo Tymoshenko, deputy head of President Volodymyr Zelenskiy’s office, said energy supplies would be significantly limited in Kyiv itself and the central regions of Kyiv, Zhytomyr and Cherkasy and the northern region of Chernihiv. Authorities had previously said power could be shut off for four hours a day to ease the strain on the generating system as technicians worked t…