At British insistence, Bermuda II furthermore contained clauses that made it illegal for any airline operating scheduled flights between the UK and the US to resort to predatory pricing or capacity dumping. Air fares were only approved if they reflected the actual cost of providing these services. Similarly, capacity increases were sanctioned on a reciprocal basis only. The reason for insisting on the inclusion of these provisions in the Bermuda II agreement was to prevent the much bigger, better financed and commercially far more aggressive US carriers from undercutting BCal with loss-leading fares cross-subsidised with profits those carriers' vast domestic networks generated, as well as to stop them from marginalising the UK carrier by adding capacity far in excess of what the market could sustain.