Cebu Philippines - Host nation Philippines said Friday that upcoming Asean and East Asia Summits on the island of Cebu have been postponed until January over worries about an incoming storm.

The decision was announced just a day after Britain, the United States, Australia and other nations warned against travel to Cebu over worries of a possible terror attack at the summits, which start Sunday.

 Officials insisted the reason for the postponement was a tropical storm bearing down on Cebu with wind speeds on Friday afternoon of more than 100 kilometres per hour, according to the Hong Kong Observatory website.

 "The decision was based on this weather disturbance and on this disturbance only," said Marciano Paynor, who heads the national committee that organised the summits.

 Paynor said ministerial meetings were expected to go ahead but the leaders' meetings of both the Association of Southeast Asian Nations (Asean) and the wider East Asian Summit would be postponed.

Meanwhile all law enforcement agencies in the country were alerted to the reported threat that water source of Cebu would be poisoned, said a ranking official of the justice department's National Bureau of Investigation (NBI). The source spoke on condition of anonymity.

Word came just before the Philippines announced that next week's Asean and East Asian summits had been postponed, but officials insisted the postponement was due to a tropical storm headed for Cebu.

The source said police were alerted to the possible threat to the water supply following two cases of mass poisoning in Manila earlier this month.

A school in the financial district of Makati was shut down while several residents of Marilao town north of Manila suffered poisoning symptoms after the spillage of poisonous chemicals at a river there.

Britain, Australia and the United States warned about travel to Cebu due to a potential terror attack on the island hosting the summits, but Manila initially denied that there was such a threat.

"We are looking into the possibility that the Makati chemical spill and chemical waste dump in Marilao were being carried out as dry runs," the NBI source told reporters.

"We are looking to see if the terrorists wanted to know how the government responds to such a situation as well as the effect of the chemical spill," the source said.

Dozens of people were hospitalized in Makati while 3,000 people fled their homes after chemical waste was dumped in the Rosario river in Marilao.

The NBI source said the bureau, the Philippine National Police, Armed Forces of the Philippines and Philippine Coast Guard were now strictly monitoring the transportation facilities in Cebu.

"While the information is not considered an A-1 info, we are not taking chances," said the NBI official.

Agence France Presse