At the National Commodity and Derivatives Exchange, refined soya oil for delivery in August edged up by 75 paise, or 0.12 per cent, to Rs 651.35 per 10 kg with an open interest of 38,540 lots.
Similarly, the oil for delivery in September was trading higher by 65 paise, or 0.10 per cent, to Rs 658 per 10 kg in 33,870 lots.
Analysts said widening of positions by traders following upsurge in demand in the physical market against restricted supplies from producing regions, mainly led to an upward trend in refined soya oil prices at futures trade.