Nigeria's media and activists fear their country is slipping into repression after the government suspended Twitter in Africa's most populous nation, where hyper-connected youth embraced the platform as a means of protest.

The decision on Friday, days after Twitter deleted a remark from President Muhammadu Buhari, has already provoked international outcry over freedom of expression and calls for protests online and on the street.

"It is very important we push back and fast, because they could go further," said a social media executive at a major TV station who asked to remain anonymous.

More than 120 million Nigerians have access to the internet, and nearly 40 million of them have a Twitter account -- 20 percent of the population, according to Lagos-based researcher NOI Polls.

France, by comparison, has only eight million Twitter users.

Nigeria's numbers are explained in part by its large and youthful population, but also the influence of its diaspora, and the online fame of its film and Afropop stars, said Manon Fouriscot, co-founder of the Afrique Connectees consultancy.

Studies also show that more than other social media platforms, Nigerians "use Twitter to give voice to the voiceless and engage government on issues that they feel are going wrong in the country in real time", according to NOI Polls.

Last October, the #EndSARS protest movement against brutality by the country's SARS -- or Special Anti-Robbery Squad -- police unit, which expanded into a call for broader reform, first exploded on Twitter before taking to the streets. 

Backed by Afropop icons with millions of subscribers, and then relayed by major international influencers, #EndSARS was the most shared hashtag in the world for two days. 

The protests that followed were the largest in modern Nigerian history, raising fears of wider instability before security forces cracked down on demonstrators.

Some Nigerian broadcasters are concerned the move against Twitter is part of a more general crackdown against the media.

The industry needs to work together to "adopt a strong and common answer," said the social media TV executive, who has several thousand followers on Twitter.

Independent broadcaster DAAR Communications announced it had filed a complaint for damage to its economic interests. Others, such as Arise TV, were still using Twitter to share news from their offices in England or the United States. 

"Twitter is, in Nigeria, and more and more on the continent, a means for civil societies to express themselves, to mobilise, to alert international public opinion," said Fouriscot, an expert in the use of social networks in Africa.

- '#KeepitOn'-
Nigeria's government said the Twitter suspension was needed because the platform had been used for activities that could destabilise the country.

With its suspension, Nigeria joins countries like China, Turkey and Myanmar that have all moved to restrict access at some time to Twitter and other Western social media.

Nigeria's government has said it is in talks with Twitter over the suspension.

Abuja's decision got a nod of support on Tuesday from former US president Donald Trump, who himself is banned from Twitter and Facebook.

"More COUNTRIES should ban Twitter and Facebook for not allowing free and open speech," his statement said.

"Who are they to dictate good and evil if they themselves are evil? Perhaps I should have done it while I was President."

The US-based social media giant has given no further update since its initial statement last week saying it was deeply concerned about Nigeria's decision. 

"We will work to restore access for all those in Nigeria who rely on Twitter to communicate and connect with the world. #KeepitOn," the statement said.

Kian Vesteinsson, a research analyst on Technology and Democracy for the Freedom House think tank, said Nigeria had already been tightening online media controls in recent years.

On Monday, the national audiovisual regulatory body NBC asked all radio and television stations in the country to delete their Twitter accounts, and warned any use of the network would be considered "unpatriotic". 

The use of VPNs to sidestep government controls on Twitter will also be considered an offence the ministry of information warned.

 'Return to dictatorship'? 
But no such law has been passed by parliament and any such move would violate basic freedoms established in the 1999 constitution, the official date marking the end of Nigeria's military dictatorships.

The UN and rights groups like Amnesty International have condemned the ban as a restriction on freedom of expression.

"Nigeria has slipped back to dictatorship," Kola Tubosun, a Nigerian linguist and writer, said in Foreign Policy magazine.

"It appears we are back in 1984 under a military regime."

That was a reference to the first time Buhari, a former general, ruled Nigeria after a coup before the return to democracy.

But Nigeria's 2.0 generation has already begun reorganising itself on social networks under the hashtag #KeepItOn and trying to organise a popular protest on June 12.

On Monday evening, on ClubHouse, a social discussion platform that is becoming increasingly popular in Nigeria, all the topics up for debate were clear: "Resisting the Dictatorship?" or "23 years ago, Abacha Died Today," referring to 1990s military ruler Sani Abacha, and "Has Nigeria learnt anything?"