Singer Beyonce, who put off a gig in Malaysia following Islamist outrage over her "gyrating moves" and "sexy outfits," was due to perform in Egypt on Friday under tight security, at the Red Sea resort of Port Ghalib.
Hamdi Hassan, a lawmaker from the Muslim Brotherhood, has written to the speaker of the house and the interior minister labeling her planned night show a "sex party" and demanding to know why she was allowed to perform.
He said the concert advertisement, in which the comely diva wears a leotard fitted with motorbike handlebars extending from her crotch and a headlight nestled in her cleavage, "threatens social peace and security."
"I do not know who agreed to this sinful, unacceptable advertisement, or indeed who agreed to these blatant sex parties," Hassan wrote, accusing the government of encouraging "sin and debauchery."
The banned party Muslim Brotherhood is effectively Egypt's main opposition party and is widely popular for its social work. It runs candidates as independents in parliamentary elections to get around the ban.
Meanwhile, a group on social networking site Facebook opposing her concert has attracted nearly 10,000 members.
Beyonce, who once told an interviewer that she "likes to dress sexy," has so far drawn about $50 million on her "I Am..." world tour, and there's no word yet on what she will be wearing.
Sharp disapproval in Malaysia
Last month, Beyonce postponed a concert outside Kuala Lumpur after an official of the Pan-Malaysian Islamic party expressed sharp disapproval.
"We are not against entertainment, but it's the way she performs -- her gyrating moves on stage and her sexy outfits. It will erode the moral values of our young people," PAS youth chief Nasr Eddin Hassan Tantawi said.
Marctensia, organizer of the Malaysian concert, had said Beyonce would tone down her attire.
It insisted the postponement was "solely the decision of the artiste and has nothing to do with other external reasons" and that a new date would be announced.
In Egypt's concert, the best tickets are going for Egyptian 2,000 pounds ($366, 246 euros), well above the means of most Egyptians.
The Muslim Brotherhood party, which calls for the establishment of an Islamic state by peaceful means, normally focuses its flak on government corruption and foreign policy, but has campaigned against what it considers prurient literature and art.
Most Egyptian Muslim women wear head scarves in accordance with Islamic custom, and the poverty-ridden country has lurched towards religious conservatism.
But the country is arguably the capital of the Arab world's film and music industries, and satellite channels with Arab pop stars in sometimes racy music videos have a wide audience.
And Western singers regularly perform in Egypt. In February, pop singer Akon, famous for his hit single "Smack That," peeled off his shirt and dove into the crowd.