LOS ANGELES (CBSLA.com) — The clerical worker strike at the ports of Los Angeles and Long Beach entered its seventh day Monday.

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The walkout has dramatically slowed activity at the nation’s busiest cargo complex as dockworkers refuse to cross picket lines set up by union clerical workers. Officials estimate the strike is costing $1 billion per day.

“We know that right now we command about 50 percent of all the imported Asia cargo through this gateway right now — that’s all at risk,” said J. Christopher Lytle, Executive Director of the Port of Long Beach.

Talks between shippers and the International Longshore and Warehouse Union continued throughout the weekend, but with no deal made.

“Most of our guys have parked their trucks and are off wondering what they’re going to do for the holiday season,” said Mike Johnson, the trucking manager at Port Logistics Group in Compton. The company services the ports of L.A. and Long Beach.

Jonson said, if the strike doesn’t end soon, the effects could be permanent, because shipping companies which divert their cargo to other ports could choose to take their business elsewhere permanently.

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Los Angeles Mayor Antonio Villaraigosa, who is currently in Colombia on a trade mission, is now calling for a mediator to help end the strike.

“I call on labor and management to start bargaining around the clock with the assistance of a federal or other mediator until an agreement is reached. The cost is too great to continue down this failed path,” he said.

“It’s a ripple effect. We have thousands of people who live in the harbor area who are not working today and it’s sad,” Los Angeles City Councilman Joe Buscaino said.

The clerical workers have been without a contract for more than two years.

The union contends that terminal operators have outsourced local clerical jobs. The shippers deny the allegation and say they have offered lifelong job security to the 600 or so full-time clerical workers.

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