Amid a raging controversy over ban on 857 websites, Internet service providers today refused to implement the government order for unblocking sites without child pornography unless they are given a specific list.

Putting the onus on the government for identifying the specific websites to be unblocked, the Internet service providers (ISPs) told the Department of Telecom they do not have any mechanism to filter out such portals on their own.

Amid a huge uproar on social media and other platforms after a ban was imposed on July 31 to block 857 pornographic and humour websites, the government yesterday reviewed its direction and restricted the ban to the sites with child pornography.

"We submit that direction given above is very vague and un-implementable, as ISPs have no way or mechanism to filter out child pornographic from URLs and further unlimited sub links of the said URLs in different-different name," Internet Service Providers Association of India (ISPAI) President Rajesh Chharia said in a letter to Telecom Secretary Rakesh Garg.

ISPs said that they "cannot monitor each and every website and check the portal from uploading any child pornographic content".

" .. we are totally against Online Child Pornography as well as abuse on women. We would continue to adhere to the practice of providing URLs to be blocked as per list provided by the Licensing Authority," ISPAI said.

The Internet industry body requested government to withdraw the order and issue a fresh order with list of specific web-links to be blocked in this regard.

"As such we will request to provide specific URLs to be blocked/disabled to all ISPs. The ISPs don't have mechanism to check the content, as the same is dynamic in nature, hence we request your good self to advise us immediately the further course of action in this regard," ISPAI said.

Despite the ban, some websites were accessible on the network of some Internet service providers.

After drawing flak from public for blocking 857 porn websites, Telecom Minister Ravi Shankar Prasad yesterday said ISPs would be immediately asked not to block those sites which do not contain any child pornographic material.

Later on Tuesday, an order by the Department of Telecom said, "the intermediaries (ISPs) are hereby directed that they are free not to disable any of the 857 URLs, as given in the list, which do not have child pornographic content."