Seven of the nine container terminals at the Port of Los Angeles and three of the six container terminals at the Port of Long Beach were closed Sunday because of the strike by about 800 clerical workers that began Nov. 27.

The Los Angeles and Long Beach ports respectively ranked No. 1 and No. 2 in North American container traffic last year, based on American Association of Port Authorities industry data.

The same year, the two ports handled 39.5 percent of the total value of all cargo container imports coming to the U.S. from elsewhere, according to Jock O'Connell, international trade economist and adviser to Beacon Economics, who was cited by the Los Angeles Times.

Due to the key roles played by the ports in the U.S. supply chain, the National Retail Federation has estimated the walkout could be costing the country's economy at least $1 billion a day.

Collective bargaining between the relevant parties -- the International Longshore and Warehouse Union, Marine Clerks Association Local 63 Office Clerical Unit, or OCU, on the labor side, and the Los Angeles/Long Beach Harbor Employers Association on the management side -- has been conducted both days this weekend.

However, there is no obvious sign of a settlement yet.

Members of the OCU had been working without an agreement since their last three-year contract expired June 30, 2010, the ILWU said. They process the huge piles of paperwork associated with the ports' container traffic.

The clerical workers' strike has been so successful because about 10,000 ILWU-represented dockworkers at the two ports have honored their picket lines, the Los Angeles Times reported.

Outsourcing of jobs is the key sticking point in the contract negotiations, OCU President John Fageaux said in a statement last week.

“It’s not about wages and benefits. It’s about outsourcing and the future of good jobs in America and our Harbor communities," Fageaux said. “We just reached the point where somebody had to stand up and draw the line against outsourcing.”

Meanwhile, the Harbor Employers Association, representing shipping agencies and terminal operators in Southern California, said in a statement Sunday that it had "offered the OCU new proposals containing further concessions in connection with the OCU's 'featherbedding' demands, the requirements that employers call in temporary workers and hire new employees even if there is no work for those individuals to perform. The OCU immediately rejected the proposals."

The association also said: "In addition to their latest concessions on staffing, the employers continue to offer wage and pension increases, an absolute job guarantee against layoffs, and a promise to maintain all other OCU benefits that the employers have previously offered -- all of which would bring the average annual OCU wage-and-benefits package to more than $190,000 over the next three-and-one-half years."