Complex sentence: The order was instituted to prevent a price war along the lines which led to the collapse of the supermarket chain H Williams in 1987, and had the effect of banning cross-subsidy and loss leaders.
Split into simpler sentences: The order was instituted to prevent a price war along the lines which led to the collapse of the supermarket chain H Williams in 1987. This has the effect of banning cross-subsidy and loss leaders.