Ukraine has imposed sanctions on former president and opposition politician Petro Poroshenko, including asset freezes and a ban on withdrawing capital from the country, a presidential decree published on Thursday said. Poroshenko, one of Ukraine's richest men who heads the largest opposition party in Ukraine's parliament, served as president from 2014 until 2019 when he lost his bid for a second term at an election won by President Volodymyr Zelenskiy. The decree did not say why the sanctions were imposed, but Zelenskiy said earlier that his security council would announce sanctions targeting people who had undermined Ukrainian national security. "The...