AMSTERDAM (Reuters) – Russian billionaire Mikhail Fridman has stepped down from the board of directors of Veon, the mobile network operator said on Tuesday, following his inclusion on a list of Russians sanctioned by the European Union. Fridman is the biggest shareholder in the Amsterdam-listed company, which operates networks in Ukraine and Russia as well as Algeria, Kazakhstan and Pakistan. He holds a stake of 47.9% via his investment vehicle LetterOne. Fridman said in a statement on Monday he would contest his inclusion on the EU sanctions list and denied he had “cultivated strong ties” to …