France has blocked five websites accused of condoning terrorism, in the first use of new government powers that came into force in February.
One of the sites – al-Hayat Media Center – is accused of links to the Islamic State group, the interior ministry said on Monday.
The site “islamic-news.info” has also been blocked since the end of last week.
The banning order was given to internet service providers, who had 24 hours to take “all necessary measures to block the listing of these addresses” under the new rules.
They were introduced as part of a package of counter-terrorism measures approved by parliament in November.
Critics argued they could breach citizens’ rights by bypassing the need for a judge to make the banning orders.
Other powers include the right to stop people travelling out of the country if they are suspected of trying to join jihadist groups.
Six French citizens aged between 23 and 28 had their passports and identity cards confiscated in February for a period of six months. The order can be renewed.
Interior Minister Bernard Cazeneuve said at the time that 40 more people were likely to be barred from travelling in the coming weeks.
He visited California last month, meeting major internet firms in a bid to improve information-sharing about online jihadist networks, and was due to meet internet company bosses again in Paris in early April.
The interior ministry has set up a warning system through which friends and family can alert authorities about potential jihadist cases.
Cazeneuve said last month that the ministry had been alerted to over 1000 cases and that “several dozen” planned trips to Syria and Iraq had been prevented as a result.