France's arrest of Durov has sent a warning to social media bosses unwilling to tackle alleged illegality on their apps.
It has also plunged French-Russia relations to fresh lows, according to some pro-Kremlin figures who have accused the United States of being behind the detention of Russian-born Durov.
A French judge put Durov under formal investigation on Wednesday for suspected complicity in running an online platform that allows illicit transactions, child sex abuse images, drug trafficking and fraud.
David-Olivier Kaminski called it absurd for Pavel Durov to be held responsible for abuses online. (EPA PHOTO)
The entrepreneur, who has French and UAE citizenships too, is also suspected of money laundering and providing encrypted messaging to criminals.
Lawyer David-Olivier Kaminski, who is representing Durov in France, said on Thursday it was "absurd to say that a platform or its boss are responsible for any abuse" carried out on the platform, and that Telegram was abiding by European laws.
Prior to his arrival on Saturday, Durov did not know about the arrest warrant that awaited him in France, a source at the Paris prosecutor's office said on Thursday.
Some commentators have speculated Durov must have known about the warrant, raising questions about why he did not stay away from France.
"He deliberately came to France where he knew he would be arrested. Why?" Gérard Araud, France's former ambassador to the United States, wrote on X.
Neither French President Emmanuel Macron nor France's foreign ministry was told in advance about plans for Durov's arrest on Saturday evening, the source at the Paris prosecutor's office said.
Macron was not scheduled to meet with Durov, the president said on Thursday during a press conference during his two-day visit to Serbia.
The source added that the French probe into Durov has no connection with the United States.
The Kremlin said on Thursday that the prosecution against Durov, whose app has nearly a billion users, should not turn into "political persecution".
Durov was granted bail on condition he pays 5 million euros ($A8.2 million) and does not leave French territory.
He will need to report twice a week to police and be at home at specific hours, a judicial source said.
Durov's arrest is a first for a CEO of a major messaging platform as tensions mount between governments and social media giants.
But it is not the first time Telegram has had a run-in with police and judicial authorities.
In 2022 Brazilian Supreme Court Justice Alexandre de Moraes temporarily suspended Telegram in Brazil, saying it had repeatedly refused to adhere to judicial orders.
At the time, Durov blamed any shortcomings on email issues and apologised.
He voiced confidence that Telegram would soon be able to "efficiently process takedown requests for public channels that are illegal in Brazil".
In Brazil's latest battle against tech impresarios, Moraes on Wednesday ordered billionaire Elon Musk, who has criticised France's arrest of Durov, to name a legal representative for his messaging platform X in Brazil within 24 hours or face the site's suspension in the country.
Meta Platforms CEO Mark Zuckerberg said this week that US President Joe Biden's administration had pressured the company to "censor" COVID-19 content during the pandemic, apparently referring to White House requests to take down alleged misinformation about the coronavirus and vaccines.
