All party leaders in the House agreed that the debate should be rescheduled as the Supreme Court's determination on the constitutionality of the bill had not yet reached Parliament, officials said.

The USD 1.4-billion Colombo Port City project, expected to play a key role in China's ambitious ''Maritime Silk Road'' project in India's backyard, is said to be the single largest private sector development in the island.

China has built the port city on reclaimed sea, adjoining the Port of Colombo.

The Colombo Port City Economic Commission Bill aims to provide for a special economic zone to establish a commission to grant registrations, licenses, authorisations and other approvals to operate business in such economic zones.

As per the schedule on Wednesday, the Supreme Court's determination of the bill was to be read in Parliament by Speaker Mahinda Yapa Abeywardena before the House was opened to debate on it. However, the determination has not yet reached Parliament.

The apex court had concluded the examination of the bill on April 23. The Supreme Court has heard 18 petitions filed against the bill by the Opposition parties and civil groups.

Some of the pleas called for the Supreme Court to order a national referendum and a vote of two-thirds majority in Parliament to pass the bill.

The bill was gazetted on March 24 and placed in the order paper of Parliament on April 9. While the Opposition parties demanded the bill be debated upon for at least three days, the government had scheduled the debate for just one day.

The Opposition has questioned the government on why was it rushing ahead with the bill.

Petitioners have branded the Port Commission Bill as a threat to the sovereignty of Sri Lanka, objecting to a clause which allows foreign persons to form the board of the commission.

Some groups have claimed that the port city could end up becoming a Chinese colony, if the bill is approved in its present form.

Sri Lanka, in recent years, has carried out various development projects with an estimated USD 8-billion in loans.

The huge Chinese loans sparked concerns globally, after Sri Lanka handed over the Hambantota Port to China in 2017 as debt swap, amounting to USD 1.2 billion for a 99-years lease.