The Copenhagen-based company said the move followed its acquisition of a 30 per cent stake in PTP, allowing it to operate a terminal at the port. It plans to shift by December, when six new berths will be in operation.

"The move to PTP represents a quantum leap for Maersk to master its own destiny and yet another step to remain in the forefront of the industry," said its Asia chief executive Flemming Ipsen.

PTP has described the deal as a "dramatic move that changes the face of the entire transshipment business" in the region.

"The deal will also mean that Malaysia will finally move to the forefront of transshipment business in Southeast Asia after having had to play second fiddle to Singapore for the last three decades," it said.

PTP said it would be guaranteed an annual volume of two million 20-foot equivalent units from Maersk Sealand from next year.

Analysts said the decision was a big boost for Malaysia but may hurt the Port of Singapore Authority (PSA) Corp, which is due to list on the stock exchange this year.

"It is a big scoop for Malaysia to actually drag away such a major client from PSA," said Sani Hamid, economist with Singapore-based Standard & Poor's MMS.

Mr Sani said PTP's offer of a stake to Maersk Sealand was the "pull factor" behind the shift, as it allowed the shipping giant to run its own show at one of the terminals.

"PTP's offer probably fell in line with Maersk's long-term goal," he said.