Two Democratic Senators have urged President Donald Trump against granting any further exemption from US sanctions on the purchase of Russian oil, contending that there is no rationale for such a move, as the war with Iran is now over. In a statement here on Tuesday, Senators Jeanne Shaheen and Elizabeth Warren said the waiver from sanctions has only helped Russia finance its "illegal war" with Ukraine. In March, the US granted a sanctions waiver to India for the purchase of Russian oil in a bid to stabilise global oil markets as the war with Iran, which started on February 28, led to a sharp increase in crude prices.