NEW YORK — Officials at 14 ports along the US East and Gulf Coasts were making last-minute preparations on Monday for a likely labor strike that could drag on the US economy just ahead of a presidential election despite last-minute talks.

Business group United States Maritime Alliance (USMX) announced late in the day that counteroffers had been exchanged with the International Longshoremen's Association (ILA), but tens of thousands of dockworkers could still walk off the job after midnight at the expiration of their six-year contract unless more concrete progress was made.