Tension is mounting as contract talks continue between the International Longshore and Warehouse Union and West Coast shipping companies, which provide a lifeline of goods and products for Hawai'i.

On Tuesday, the Pacific Maritime Association accused dockworkers of "disruptive job actions" at terminals in Los Angeles and Long Beach.

The association said workers took part in an organized work slowdown that resulted in a 20 percent to 30 percent drop in productivity.

A six-year contract that covered 26,000 West Coast dockworkers in California, Oregon and Washington expired July 1. The union and the Pacific Maritime Association, which represents 71 shipping companies, are negotiating a new three-year deal.

The PMA said workers coordinated breaks, operated vehicles more slowly than normal, and made "brief delays" while placing containers on trucks.

"The cumulative impact of these actions is to slow operations incrementally, but significantly," the PMA said in a statement. "As time goes on, the impacts threaten to become even greater."

ILWU spokesman Craig Merrilees said the PMA is overreacting and he questioned management's assertion that productivity was affected.

"The ports are open, the cargo's moving, workers are on the job, companies are making tons of money and the negotiations are moving forward," Merrilees said. "These negotiations started on March 17. It's been quite a while and it's understandable that people are getting a little antsy and impatient. But the complaints amount to pretty small potatoes and we shouldn't be making a mountain out of a molehill."

So far, the alleged slowdown has had little impact on ships headed to Hawai'i. Jim Andrasick, president and chief executive officer of Matson Navigation Co., said one vessel left Long Beach three hours late on Monday as a result of labor action.

"It's not what I would call severe. We can make up part of that time in transit," he said. "But we run on a very tight schedule because our customers demand it and expect freight at a certain hour of the day, so it does have a disruptive effect."

Andrasick said the slowdown was a "step backwards" in negotiations. Matson is the largest ocean cargo carrier to Hawai'i.

On Sept. 29, 2002, a work slowdown led the shipping companies to lock out the dockworkers for 10 days. The work stoppage shut off shipments to the Islands until the PMA granted a lockout exemption for ships headed to Hawai'i and Alaska about a week later.

Both Andrasick and Merrilees said they don't believe a similar work stoppage is imminent.

"I don't want to give the impression that there would be, because as I said we're still optimistic that both sides will come to terms," Andrasick said.