BP is expected to report that its profits have more than halved as the price slump continues to take its toll.

The energy giant, which is due to publish its third quarter results on Tuesday alongside rival Royal Dutch Shell, is forecast to have made underlying profits of $780m (£640m) in the three months to September, down from $1.8bn in the same period last year.

The drop reflects lower oil prices, which averaged less than $46, compared with more than $50 the previous year.