McDonald’s Holdings Co (Japan) Ltd has embarked on the emergency measure of only offering small-sized french fries to customers as a protracted labor dispute at U.S. West Coast ports has contributed to long delays in imports.

The fast-food chain said it was importing more than 1,000 tonnes of frozen fries by air, which began arriving last Monday and had begun routing another 1,600 tonnes through ports on the U.S. East Coast which should begin arriving in late January.  Those steps alone, however, are not sufficient to prevent a shortage.

rToyama said the company, which has 3,100 stores in Japan, was not placing any limit on the number of small-sized fries a customer may buy but the resumption of medium-sized and large-sized fries remains unclear. She declined to comment on the impact on earnings.

The cargo backups at U.S. West Coast ports dragged on into a third month amid industry reports of prolonged shipment delays for goods ranging from yoga apparel and rice to NBA bobblehead collectibles and frozen french fries.

Cargo that normally takes two to three days to flow through the affected ports, accounting for nearly half of U.S. maritime trade and over 70 percent of imports from Asia, now faces lag times of up to two weeks, the National Retail Federation said.  The congestion has been most pronounced at the twin ports of Los Angeles and Long Beach, the nation’s two busiest cargo hubs, where marine officials reported 11 ships anchored on Thursday waiting for berths to open.

The number of freighters kept waiting outside the two ports has fluctuated from about eight to 18 on any given day since the slowdown began there around mid-October, said port of Los Angeles spokesman Phillip Sanfield.  Smaller backups have hit other West Coast ports, including Seattle and Tacoma in Washington state.

The slowdowns have coincided with prolonged labor talks between 20,000 dockworkers and the Pacific Maritime Association, representing terminal operators and shipping lines at 29 West Coast ports. Their latest contract expired June 30.

Management has accused the International Longshore and Warehouse Union of orchestrating some slowdowns on the docks to bolster its leverage at the bargaining table.  Union officials deny organizing protest delays but acknowledge individual dockworkers may have acted out of frustration over the pace of contract talks.

Other factors cited are a shortage of tractor-trailer chassis used for hauling cargo containers from the ports, a situation created when shippers decided to sell off their chassis to equipment-leasing companies.

Union and port officials also cite record import levels at the peak cargo season, rail service delays and the advent of super-sized container vessels delivering greater cargo volumes.