Mumbai, Aug. 28 -- The Indian rupee rose by 6 paise to close at 87.63 (provisional) against the US dollar on Thursday aided by a weaker greenback and a decline in crude oil prices. However, concerns over additional US tariffs on Indian products, which kicked in on Wednesday, and a decline in domestic equity markets capped gains in the local unit. Indian shares fell sharply on Thursday as traders waited to see how New Delhi responds to pressure from Washington to stop buying Russian oil after the 50 percent tariffs levied by the U.S. on Indian goods came into effect on Wednesday. The benchmark BSE Sensex fell 705.97 points, or 0.87 percent, to 80,080.57 as trading resumed after a holiday on Wednesday for celebrating Ganesh Chaturthi. The b...