The US Federal Maritime Commission (FMC) is keeping a close eye on three major liner alliances to ensure fair competition among operators.

It has taken this watchful stance at a time when containership rates have hit all-time highs, to the detriment of importers and consumers.

The average cost to ship a container from China to the US West Coast almost quadrupled this year to about $14,500 per 40-foot equivalent unit due to consumers shopping online while in pandemic lockdown.

Meanwhile, liners leave empty boxes at US ports to rush back to China and reap the high China-US rates, leaving less space for boxed goods that are stacked sky-high at terminals.

The three alliances — 2M Alliance, Ocean Alliance and THE Alliance — ship about 80% of seaborne containerised goods and 95% of those on the East-West trade lanes, according to the International Transport Forum.

"The FMC will continue to use all available mechanisms to monitor the three major alliances for anticompetitive behaviour and will take any action necessary to ensure fair competition among individual carriers," FMC chairman Daniel Maffei told TradeWinds.

"As the chairman of the agency with just one voting member, I appreciate the attention being paid to these important issues by the Biden-Harris administration and believe it's consistent with what the FMC is working on."

The liner operators that make up the three alliances are AP Moller-Maersk, Mediterranean Shipping Co, Hapag-Lloyd, ONE, Hyundai Merchant Marine, Yang Ming Marine Transport, Cosco, CMA CGM and Evergreen Line.

"This lack of competition leaves American businesses at the mercy of just three alliances," the White House said in a blog on its website.

"Retailers are charged fees for their container remaining on the docks, even if there is no way to move their containers.

"If the alliances decide to not accept exports, agricultural exporters will not be able to fulfil their contracts, and farmers' perishable products may be left to rot."

President Joe Biden's executive order on promoting competition in the American economy encouraged the FMC to enforce prohibition against ocean carriers charging unfair fees.