(Reuters) - Mercury Public Affairs, which did work for Paul Manafort related to his lobbying for a pro-Russian Ukrainian political party, is cooperating with a federal probe into Russia’s possible interference in the 2016 presidential campaign, a Mercury partner said. “Mercury takes its obligations to follow all laws, rules and regulations very seriously. Mercury has and will continue to fully cooperate with the Office of the Special Counsel in its investigation,” Michael McKeon told Reuters in an emailed statement. 