TEHRAN, April 30 — Female sports fans can attend games at Iran's stadiums for the first time in nearly three decades, after President Mahmoud Ahmadinejad unexpectedly lifted a ban last week that had prohibited women from entering stadiums.

Senior clerics and conservative members of Parliament criticized the decision, saying that frequent hooliganism at sporting events made them inappropriate for women.

But Mr. Ahmadinejad said women will promote better behavior.

"Certain prejudices against women have nothing to do with Islam," he said on Friday, several days after lifting the ban, in a speech that seemed to present him for the first time as a supporter of expanded rights for women. "Unfortunately, whenever there is talk of social corruption, fingers are pointed at women. Shouldn't men be blamed for the problems too?"

Soccer matches are the most popular sporting events in Iran. Women had been demanding the right to attend games for over a decade, but officials, including the former reformist president, Mohammad Khatami, denied their requests.

A strict dress code for women and segregation of the sexes has been enforced since the 1979 Islamic revolution. Mr. Ahmadinejad has specified that the best seats in stadiums to be allocated to women and families in order to adhere to the segregation code.

"I respect him for this move," said Siamak Namazi, a political analyst at Atieh Bahar Consulting. "It was a gutsy move because he can lose some of his conservative supporters who voted for him," he added.

Advocates of greater rights for women welcomed his decision, although they acknowledged that the move was also a way to increase his popularity among women at a time when he needs to bolster his support inside the country.

"Even if the pressure by clerics in Qum forces Mr. Ahmadinejad to back down, his decision will always be considered as a winning card or him," Shadi Sadr, a lawyer and a feminist, wrote on Saturday in the daily reformist newspaper Shargh.