LOS ANGELES — Contract negotiations were postponed late yesterday between office clerks at the nation's largest port complex and their employers because the lead negotiator for the companies needs to attend to a family medical issue, representatives for both sides said.

Talks were scheduled to resume tomorrow morning.

The parties have been at the bargaining table since Sunday afternoon, attempting to reach a settlement and avert a possible shutdown of the docks at the ports of Los Angeles and Long Beach.

The office clerical unit of Local 63, a division of the International Longshore and Warehouse Union, submitted its latest proposal last night, and by the time the talks broke off, the shipping companies and terminal operators were considering it.

The 15,000-member ILWU has indicated that longshoremen would honor picket lines if the 750 clerks strike.

That would effectively shut down loading and unloading operations at the neighboring ports of Los Angeles and Long Beach.

A strike could potentially disrupt the flow of goods to Hawai'i, which relies heavily on shipments from the two ports. However, during past labor disruptions at the the Los Angeles-Long Beach port complex, some Hawai'i-bound goods were rerouted through the port in Oakland.

While the local 63 clerical union president, John Fageaux, declined to provide specifics of the union's latest proposal, he said there were sticking points on wages, job security and health and pension benefits.

He said the union initially decided to submit a "last, best and final offer" yesterday but changed its mind later in the day.

Steve Berry, lead negotiator for the 14 marine terminal operators and other firms that employ the office clerks, said one counterproposal was given to the union around 6 p.m.

"We're working hard. We just keep going," said Berry, who had to attend to the family medical issue.

The port complex accounts for 40 percent of all the cargo container traffic coming into the United States. The clerks work at marine terminals and handle bookings for the export of cargo and other transport documents.

Under their most recent contract, full-time, port clerical workers earned about $37.50 an hour, or $78,000 a year. They also receive a pension, healthcare benefits free of premiums, and 20 paid holidays a year.

Berry said the employers' latest offer included raises that over the life of a three-year contract would bump the employees' hourly pay to $39.50; the union is seeking increases that would equal $53 per hour by the last year of the contract.