Magetan, Indonesia - Muslim clerics in Indonesia's East Java province Friday banned the faithful from gossiping and flirting on social networking websites such as Facebook and Friendster.

The clerics also urged Facebook and Friendster to curb what they called "lewd and pornographic" content and warned that they would request the government to block the sites if their call went unheeded.

Hundreds of Muslim scholars from the Nahdlatul Ulama, the country's largest Islamic group, met Thursday and Friday to discuss the impact of the exploding popularity of Facebook and other social networking sites among young Indonesians.

They clerics fear that getting in touch on social networking could lead to illicit sex and extra-marital affairs.

"Communicating through Facebook, Friendster or other social networking sites is allowed only for Islamically beneficial purposes, such as helping friends," said Abdul Muid Shohib, a spokesman for the clerics.

"Exposing other people's dirty laundry, gossiping and doing other un-Islamic activities are haram [religiously forbidden]," he said at the end of their meeting held in Kediri district.

Shohib said Friendster contained more lewd images than Facebook.

"If there is no change within one month, we will ask the government to block access to Facebook, Friendster and other sites," he said.

The clerics' ruling is not legally binding in the world's most populous Muslim, but officially secular, nation.

More Indonesians have gained access to the internet in recent years thanks to cheaper connection costs and devices.

Facebook is the most popular website in Indonesia, followed by the local versions of Google and Yahoo, according to website tracker Alexa.(dpa)