Crude oil prices on Monday increased Rs 55 to Rs 6,401 per barrel in futures trade as participants widened their positions following a firm spot demand. Globally, West Texas Intermediate (WTI) crude oil was up by 0.82 per cent at $76.51 per barrel, and Brent crude traded 0.57 per cent higher at $81.08 per barrel in New York. On MCX, crude oil for December delivery traded higher by Rs55 or 0.87 per cent at Rs6,401 per barrel in 13,059 lots. Analysts said raising of bets by participants kept crude oil prices higher in futures trade.