Previously seen as, quote, unrealistic. his comments coming a day after the russian president, vladimir putin, sent shock waves through europe by cutting off natural gas supplies to poland and bulgaria over their refusal to pay in rubles. two leading european energy companies said on thursday they re working on a way to make the ruble payments without running afoul of sanctions. now, germany s uniper and austria s omv confirmed they re working on a sanctions compliance solution. on wednesday, hungary said it will use moscow s payment scheme to pay for its oil and gas. a former senior official of gazprombank says he resigned from his post and left russia as an act of dissent after the invasion of ukraine. igor volobuev was a vice president at gazprombank who worked at the company for six years. he spoke to cnn s nina dos santos. here is her report.