U.S. Ports from Maine to Texas could shut down Tuesday if a union representing about 45,000 dockworkers carries through with a threat to strike.

Time is running out to avoid a work stoppage at ports along the entire East and Gulf Coasts in what could become the most disruptive strike to the US economy in decades. Members of the International Longshoremen’s Association are set to go on strike at 12:01 am ET Tuesday at three dozen facilities spread across 14 port authorities.