SINGAPORE (AFP) -- Singapore, the world's busiest container port, is aiming to double capacity to 50 million 20-foot container boxes by 2018 as world trade booms, a senior government official said.

"If world trade continues to boom and fuel container shipping growth of about six percent per year, we estimate throughput will double in about 12 years' time," Minister of State for Transport Lim Hwee Hwa said in remarks released late Thursday.

"For planning purposes, we have therefore made preparations for our ports to have the capacity to handle 50 million twenty-foot equivalent units (TEUs) by 2018," she said in response to questions in Parliament.

Singapore moved 23.2 million 20-foot containers in 2005 to regain the position as the world's busiest container port from Hong Kong for the first time since 1998, Lim said.

Throughput expanded almost nine percent from 2004, faster than its regional rivals Hong Kong as well as Port of Tanjung Pelepas and Port Klang in Malaysia. Singapore retained its position as the world's busiest port in terms of shipping tonnage with 1.115 billion gross tons last year and was the top bunkering port worldwide, Lim said.

Vessel tonnage measures the volume of merchant ships arriving in a country.

Singapore's PSA International, the world's second biggest container port operator after Hutchison of Hong Kong, reported Wednesday net profit rose 20.2 percent in 2005 from the previous year, lifted by a boom in Asian trade.

The net profit came in at 1.058 billion Singapore dollars (653 million U.S.) and compared with 880.5 million dollars in 2004. PSA's operations in its home base contributed strongly to the group's net profit.

PSA International last month tried to further expand its global reach when it mounted a bid for British port giant Peninsula and Oriental Steam Navigation Company (P and O).

But PSA abandoned its 3.545 million British pound (6.2 billion U.S. dollar) bid after rival DP World of Dubai made a higher offer which valued P and O at 3.92 billion pounds.

"There are still many opportunities in the global marketplace of ports. I am sure PSA will continue to be on the lookout for attractive projects to increase its international footprint," Lim said.

PSA, owned by Singapore's state-linked investment company Temasek Holdings runs ports in Singapore, Belgium, Brunei, China, Hong Kong, India, Italy, Japan, the Netherlands, Portugal, South Korea and Thailand.