Nauru's opposition and refugee advocates have slammed a government ban on Facebook, calling the move an act of "dictatorship".

The comments came after the government directed Digicel, the nation's internet service provider, "to start blocking applicable websites", which the opposition said includes the social networking site.

In a statement, the government cited moral and religious grounds for the ban, as part of a broader crackdown on "internet sites that show pornography, particularly those featuring children".

But opposition MP Matthew Batsiua told Pacific Beat he considers the move a way to stop Nauruans from using Facebook to criticise the government.

"The real agenda here is curbing the rights of people to access social media," he said.

He said people in Nauru usually use Facebook to express dissent and keep in touch with family overseas.

Mr Batsiua dismissed the government's suggestion that the ban was implemented on moral grounds.

"The first reason they gave [for the closure] was due to a technical problem. Now it's all about porn," he said.

"This is all about [justice minister] Adeang and his cronies being worried about the ever increasing number of people who have taken to social media to criticise his dictatorial style, which even the president is either unwilling – or too scared – to rein in."

Radio Australia has attempted to contact the Nauru government for comment, but they have not responded.

Claims of a dictatorship

"There has been a growing concern ... on Facebook about criticism against this government for a lack of scrutiny," Mr Batsiua said, a trend which has concerned the government.

"A lot of people on Facebook are calling our government a dictatorship.

"I mean the behaviour that we have seen in shutting out members of the opposition, having an ineffective parliament where basically there's no scrutiny or debate on policies and activities, now curbing social media ... I'm just spelling out what it is."

Ian Rintoul from the Refugee Action Coalition agreed, saying the government is "not far short of being a dictatorship".

He dismissed claims by the government that they are simply trying to crack down on internet pornography.

Shutting down Facebook will severely impact refugees in the detention centre who use the social media network to communicate with the outside world, Mr Rintoul said.

"We've seen even in the treatment of refugees ... the total power rests with commissioner and there's no obvious way of appealing against the commissioner's decisions about whether protests are allowed or disallowed," he said.

Mr Rintoul said the government has been issuing decrees on where people can protest and "the ability to arrest ... assemblies three or greater now extends to public areas and that effectively means inside the refugee compounds itself".

Locals versus refugees

Mr Rintoul said there is a growing disquiet among people in Nauru as they feel they are "treated the same way as refugees".

"So rather than unity ... we're more likely to see increasing dissent inside Nauru partly as a result of the way in which the collaboration with the Australian Government has enriched quite a few people on Nauru but it certainly hasn't enriched the general community," he said.

The opposition said Mr Adeang had revoked the visa of Digicel's Nauru manager Lorna Roge while she was off the island on business.

"She joins the growing list of expat personnel who have been shunted off Nauru for no given reason other than Adeang doesn't like them," Mr Batsiua said.

"It's a disgrace and the sooner this government calls an election so we can return Nauru to democracy, the better.

"Meanwhile it would be interesting to know how other countries in our region view this latest sorry act of censorship by this Nauru government."