India's telecommunications authorities gave service providers the go-ahead on Wednesday to restore access to most of the 857 websites that had been blocked, a ministry spokesman said.

"ISPs are free to allow access to the previously banned websites, which do not have child pornographic content," telecoms department spokesman N. N. Kaul told the AFP news agency.

The government moved over the weekend to shut down the list of flagged adult sites on "morality and decency" grounds. It said restricting access to pornographic content was a necessary step after the Supreme Court raised concerns last month that not enough was being done to crack down on child porn on the Internet.

Censorship of Internet content is common in India, but the order to block hundreds of adult sites was the first big crackdown on Internet pornography.

Uproar on social media

The ban sparked a debate about Internet freedom and an outcry on social media, with the hashtag #pornban trending on Twitter's India domain. Best-selling author Chetan Bhaglat, who had criticized the ban, welcomed Wednesday's reversal.

Others were more apprehensive. Some service providers complained the onus had now shifted to them to control access to child pornography.

"This is a very vague order. There is no clarity and until we don't get clear answers, we will keep the websites blocked," Rajesh Chharia, head of the Internet Service Providers Association of India, told AFP.

India has been accused of encroaching on online freedom in the past. In 2011, the government urged social networks to screen content and remove offensive material. One year later, authorities ordered dozens of Facebook and Twitter accounts to be blocked for spreading rumors.

India has 350 million Internet users - the second largest number after China - and use of smartphones. Social media use is rising rapidly in the country.

nm/sms (Reuters, AP, AFP)