The union and employers’ groups have been in near-daily negotiations for a month and sources with knowledge of the talks say there is optimism that they will be concluded without disruption, though discussions are likely to continue beyond the deadline.

However, the Pacific Maritime Association (PMA) and the International Longshore and Warehouse Union (ILWU) remain divided over key issues, particularly the impact of the Affordable Care Act on the dockworkers’ healthcare plans.