With a strike by unionized longshoremen at Eastern and Gulf Coast container ports looming, President-elect Donald Trump doubled down on his opposition to automation over the weekend.

On Saturday, Trump retweeted to his more than 8 million followers on his Social media platform Truth Social a Facebook message from Dennis Daggett, executive vice president of the International Longshoremen's Association, praising Trump's support for the union in its long-running contract battle with employers at container ports on the East Coast and Gulf Coast.

The announcement came after President-elect Trump met with Daggett and his father, Harold Daggett, president of the International Labor Organization, at his Mar-a-Lago resort in Florida on Thursday and expressed support for the union's performance in the contract dispute after the talks. Before that, Trump retweeted the message.

"Yesterday, I had the privilege of meeting with President-elect Donald Trump and I wanted to share an experience I could never have dreamed of," Dennis Daggett wrote in his Facebook post. "In my entire career, I have never met a politician - let alone a president of the United States - who truly understands the importance of the work that our members do every day. But yesterday, President-elect Trump not only showed that understanding, he also showed the utmost respect for our members' hard work, sacrifice and dedication."

Trump's comments come as contract negotiations between the International Longshoremen's Association and employers represented by the United States Maritime Union (USMX) have stalled. The union claims automation will kill jobs, while the American Maritime Alliance says the technology is urgently needed to improve the global competitiveness of container handling at ports.

Despite the union's prominence and leadership in the war of words, executives from USMX member companies, including foreign ocean shipping companies, were reluctant to represent their groups during negotiations.

The two sides have until Jan. 15 to reach a new agreement, when a current contract extension covering tens of thousands of union workers at dozens of ports from Massachusetts to Texas expires.

In October, unions called a three-day strike that brought container and ro-ro shipments to a standstill. Acting Labor Minister Julie Tsu brokered the end of the strike, with both sides agreeing to extend the strike and a 62 per cent pay rise for workers, while negotiations were held on container usage charges and other details of a new six-year general contract.

But the ILA ended negotiations over the employer's request to include semi-automatic cranes in the new contract. While the union says USMX wants to cut jobs, it also claims the cranes pose a safety risk to ports and shipping.

If no new agreement is reached before the extension expires, the pay increase will be canceled.

Despite Trump's public support for unions, there has been no indication of what action he would take in the event of a prolonged strike.

Before the election, President Biden said he would not intervene in the strike. The Taft-Hartley Act gives the president the power to terminate a strike and order a cooling-off period if it is proven to seriously harm U.S. interests.

2002 President George W. Bush invoked the Taft-Hartley Act to end a strike by members of the International Longshore and Warehouse Union at West Coast ports.

Shippers have been bringing forward imports for months in anticipation of a possible strike, as well as Trump's proposed tariffs on China, while shipping companies have announced service changes to cope with the disruption.

In its advice to customers, CMA CGM said: "In the event of a strike, we expect vessel operations to stop at 00:01 on 16 January 2025. Our dedicated teams are working on contingency plans to ensure that all... Operations are completed before any labor disruption.

"In the event of a shutdown, U.S. East Coast and Gulf Coast terminals would cease operations, resulting in the suspension of gate and rail services." As the January 15 date approaches, you will receive more details. Similarly, the docks and nearby warehouses will not be open for return of empty containers. Please keep your empty containers until the docks and warehouses reopen. Upgrades and urgent questions can be sent to your designated Customer Solutions contact."