PoliticsRosneft protests over US sanctions on trading unitFresh sanctions come as Russian state-controlled oil producer struggles to grow oil and gas output and faces declining profitabilitySharp response: Venezuelan President Nicolas Maduro holds a sword, given as gift by Rosneft chief executive Igor Sechin during the signing of agreements in Caracas in 2016Photo: AFP/SCANPIXVladimir AfanasievMoscow