BIG carrier alliances will bring much-needed stability to supply and demand problems on east-west trades, according to London's Drewry Maritime Research.

Adjusting capacity to meet seasonal demand will become easier when four alliances are responsible for 98 per cent of capacity on the Asia-Europe trade from January, said the report.

With containerships getting bigger, particularly on the Asia-Europe route, there is a trend to cancel individual sailings rather than whole services in winter.

The bigger the alliance, the smoother the schedule disruption caused by such an omission, and the more alternative sailings there are to cater for roll-overs, said Drewry.

But Drewry analysts warned that most exporters demand a steady supply of vessel capacity and cannot easily adjust production to meet the requirements of ocean carriers.

It is of course illegal for consortia to manage capacity to avoid such situations, yet there is nothing to stop them from keeping an eye out for service cancellations or capacity upgrades among rivals.

Drewry states that this can and almost certainly is happening today, meaning carriers are only likely to become better at fine-tuning capacity as the number of shipping lines continue to reduce.