Some U.S. Democrats are calling for the impeachment of President Donald Trump over reports that he asked his Ukrainian counterpart to launch an investigation into Hunter Biden's role at Burisma to damage his father, one of Trump's political rivals.
"Changes to the board of Burisma Limited, which are currently the object of international attention, took place only in May 2014, and therefore are not and never were the subject of (the anti-corruption bureau's) investigation," the bureau's statement said.
