Lady Gaga's tour of Asia has been hit with another blow after protest groups in the Philippines called on officials to follow Indonesia's lead and ban the pop star from performing.

Dozens of hardline Christians took to the streets of capital city Manila on Friday for a 'Stop the Lady Gaga concerts' rally, piling pressure on organizers to axe the upcoming shows.

The protesters, from the Biblemode Youth Philippines group, say they are offended by the raunchy Poker Face hit-maker's music and promos, and singled out her hit track Judas, branding it blasphemous.

Gaga is due to perform in the city on Monday and Tuesday, and Pasay City Mayor Antonino Calixto has urged promoters to ensure she obeys the country's strict concert rules, which ban nudity and lewd acts, according to the Associated Press.

In a statement, he says, "Although we respect artistic and musical expressions, I won't allow anyone or any group to provide acts which may be questionable in a way at any venue under my jurisdiction.

"We reminded the producers of Lady Gaga's concert that the show and the event as a whole shall not exhibit any nudity or lewd conduct which may be offensive to morals and good customs."

Gaga's gig could also face problems even if the protesters fail in their bid to ban her - they've vowed to file a lawsuit against the singer if she performs Judas at the shows in Manila.

The Asian leg of Gaga's Born This Way Ball tour has been dogged with problems - uncertainty still hangs over her planned gig in Jakarta, Indonesia next month after officials withdrew her performance permit, and her show in Seoul, South Korea was hit with protests and a ban on under-18s.