Aliens may be barred entry because of public health, safety, and national security concerns

Dear PAO,

I have a fiancé who arrived in Manila last month. I was not able to see him, though, because he was asked to go back to his country of origin. It was not clear to him why he was not allowed to enter the Philippines. Can this really be done to foreigners? Shouldn’t we welcome them as part of the government’s effort to promote tourism?