Panama's Supreme Court last month invalidated Hutchison's contract following repeated threats from President Donald Trump that the United States would seek to reclaim the waterway, which he said was in effect controlled by China.

The Panama Maritime Authority (AMP) then said port operator APM Terminals, part of the Danish Maersk Group, would temporarily take over operation of the Balbao and Cristobal ports on either side of the canal from the Panama Ports Company (PPC) -- a subsidiary of CK Hutchison.

The canal, which handles about 40 percent of US container traffic and five percent of world trade, was built by the United States, which operated it for a century before ceding control to Panama in 1999.

The PPC has initiated arbitration proceedings, and in a statement Thursday, CK Hutchison warned that handing control the ports to Maersk "will cause damages... and will result in recourse against APMT."

Since 1997, Hutchison had managed the ports of Cristobal on the interoceanic canal's Atlantic side and Balboa on the Pacific side.

The concession was extended for 25 years in 2021.

Last month the Supreme Court ended the contract on grounds that laws which allowed CK Hutchison Holdings to operate two of the five ports of the canal were "unconstitutional."

Panama has always denied Chinese control over the 50-mile waterway, which connects the Atlantic and Pacific oceans and is used mainly by the United States and China.

Hutchison considers the January court ruling to be unlawful.

In its statement Thursday, the company said it would "continue to consult with its legal counsel regarding all available recourse including additional national and international legal proceedings against the Republic of Panama and its agents and third parties colluding with them in this matter."

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