Container cargo movements on Thursday returned to 70 percent of normal at the Port of Pusan, as more Korean truck drivers abandoned a weeklong strike.

The port was moving 54 percent of its normal container traffic a day earlier. The Port of Gwangyang was faring even better, moving 84 percent of its normal container volume, according to the Ministry of Maritime Affairs and Fisheries.

About one-third of container cargo drivers and three-quarters of cement truckers have returned to work, the government estimates. Officials say more than 50 percent of container truck drivers and freight handlers must return to get the national cargo system back to near normal.

The main organizers of the stoppage insisted that none of its container-driver members has returned.

"If the government continues to suppress and threaten us, we will consider launching a stronger protest, such as using vehicles to block roads," a statement from the strikers said.

They are demanding a 30 percent increase in haulage fees, while management is offering 13 percent. The drivers also want an industry-wide deal for container and cement drivers, which companies reject because of the great disparities in the operations.

The return to work appears to be mainly among non-union drivers, concerned that truck-operating companies would cancel transport contracts and by the government's plans to cut fuel subsidies. They government granted the subsidies after a similar 15-day strike in May.

Police, meanwhile, were thwarted in their attempt to arrest 16 of the key leaders of the walkout at the Seoul offices of the umbrella Korean Confederation of Trade Unions when hundreds of workers posted a guard around the building. Another mass protest was set for Thursday at the Parliament building.

"President Roh Moo-hyun failed to keep his election platform to boost workers' rights, caving in to business demands for a growth policy at the expense of justice and fair distribution of wealth," the KCTU said.

Roh has refused to mediate in the dispute, saying it must be resolved between the parties. Government moves to end the May strike came under fire from business for caving in to strikers' demands.

The current strike is estimated to have resulted in lost exports valued at $530 million.

By P.T. Bangsberg