(ANSA) - BELGRADE, DEC 19 - In light of US sanctions on Serbian oil company NIS, Russian giant Gazpromnyeft is negotiating the sale of its ownership stake, Russian President Vladimir Putin, said, calling for a "common solution" in this regard. "We understand what is happening with NIS. We have an intergovernmental agreement, and we believe the friendly Serbian leadership will take it into consideration," Putin said at the year-end press conference. "We have an idea about how we can move forward together. We are working on it, and I hope to find a solution," the president said, as quoted by Belgrade media. (ANSA).