The union that has closed port terminals across a swathe of the US coastline and threatened to cripple supply chains has reached a tentative deal with employers that will send dockworkers back to their posts.

The International Longshoremen’s Association (ILA) and the employers’ group covering vehicle and container ports on the US Atlantic Seaboard and Gulf Coast said the tentative agreement on wages comes with an extension of their existing contract until 15 January.