REUTERS The U.S. dollar gained 38 kopecks, amounting to 65.38 rubles, the Moscow Stock Exchange data show. The euro rose 43 kopecks to 72.60 rubles. Over the past two months the Russian national currency has weakened from 49.2 rubles per the U.S. dollar to 65 rubles per the U.S. dollar, and against the euro – from 55 rubles to 72 rubles. The Russian stock market has also fallen at the Monday opening. The MICEX index dropped by 0.54% to 1703.24 points. The RTS index was down by 1.82% to 819.94 points. The collapse of the ruble and the Russian indices comes amid falling oil prices. North Sea Brent Blend futures for October delivery dropped this morning by 1.14% to $48.63 per barrel, while WTI crude oil futures for September delivery were down by 1.25% to $41.97 per barrel. The global oil market is already in surplus by about 3 million barrels a day, with Saudi Arabia and Iraq responsible for OPEC&#39;s oversupply in the past six months, Iran&#39;s state-run Islamic Republic News Agency reported Sunday. Iran can boost output by 500,000 barrels a day within one week after sanctions are lifted, Oil Minister Bijan Namdar Zanganeh said earlier this month, according to Bloomberg.