MANILA, Philippines — The Philippine health secretary urged Filipino boxing idol Manny Pacquiao to postpone his triumphant return to his homeland after beating Ricky Hatton to help prevent the spread of swine flu from the United States.

Health Secretary Francisco Duque III told reporters the World Health Organization made the "strong recommendation" for Pacquiao and his entourage to remain in Los Angeles and observe self-quarantine until next week because the virus was found to have spread in that US city.

Duque said there are concerns that Pacquiao's motorcade in Manila and other parts of the country could pose a risk of spreading the virus if he or anyone in his group is infected. The Philippines has yet to confirm its first case of swine flu.

Duque said the WHO has reported a "third-generation human-to-human transmission" of the virus in Los Angeles, citing the case of a Mexican who infected another individual, who in turn contaminated a third person.

"Since Manny Pacquiao is in Los Angeles ... it is better to be conservative," he said. "Part of our message to them is that beginning today, they shouldn't be going out anymore. They should impose self-quarantine."

He said health authorities have been trying to contact Pacquiao to try to convince him and his party not to fly back to Manila earlier than Tuesday because it will take about five days for symptoms to appear.

"What we have to do is to convince them the best way we can. I cannot imagine that they will refuse," he said.

Pacquiao, his wife, mother and others in his entourage drove from Las Vegas to Los Angeles to celebrate his second-round knockout victory Sunday over Hatton.

The government declared a "national day of celebration" on Friday to welcome Pacquiao back. Weather forecasters, however, predict it could also be a rainy day in Manila from an approaching storm.

Duque said 10 people have been under observation for swine flu in the Philippines since May 1 and five of them have already been cleared of the virus.

Of the remaining cases, two are Filipinos who returned separately from Ireland and the United States, two boys aged 9 and 12 from South Korea and a 26-year-old woman from Britain. They are under observation at different government health facilities.

Duque also said he will chair a meeting in Bangkok, Thailand, starting Thursday of health ministers from the 10-member Association of Southeast Asian Nations, plus those from Japan, China and South Korea.

He said the health ministers will try to craft a binding resolution on pandemic preparedness and action plans to be submitted to the world health assembly in Geneva, Switzerland, on May 18.