The world's busiest container ports of Hong Kong, Singapore and Shanghai are reportedly facing increased congestion, which raises fears of slower cargo movement and unreliable shipping schedules.

"There isn't a lot of margin for error in the system," said Ron Widdows, chairman of the Transpacific Stabilisation Agreement in a statement, reported Bloomberg.

The congestion has been blamed on growing Intra-Asia and Asia-Europe trade ahead of the peak shipping season. The report noted that in June alone, TSA member container lines handled 16 per cent more boxes than in the same month a year ago.

"Forecasts from our customers indicate a healthy second half for the container shipping sector,"' said Mr Widdows, who is also chief executive officer of Neptune Orient Lines' container shipping arm, APL Ltd.

In a bid to overcome the possibility of shipment delays, the 14-member group intends to raise the capacity deployed on routes to the US east coast by a total of about 70,000 FEU this year to meet demand for 2008, the report added.