One-day data block introduced on Russian SIM cards being brought back into country

The Russian authorities have begun blocking mobile phones being brought back into the country from abroad for 24 hours in an attempt to undermine Ukrainian drone strikes, the Ministry of Digital Development, Communications and Mass Media announced on Monday.

The ministry said that the measure had been applied in test mode on Monday, with mobile internet and SMS messages being blocked for 24 hours for anyone returning to Russia from abroad or for those who had not used their SIM card for 72 hours.

While users should receive a notification informing them of the block via SMS, the ministry did say that internet access could be restored before the end of the 24-hour cooling-off period by completing a captcha sent by individual telecom operators.

Investigative news outlet Verstka said that two of Russia’s largest telecom operators, MegaFon and Beeline, were already warning their customers about the temporary suspension of their mobile data, but said that the Beeline link to restore access to data services did not appear to work.

The ministry said the measure had been introduced to avoid SIM cards being used to navigate Ukrainian drones. The cooling-off period was first reported by Russian business daily Kommersant on Friday, with some experts warning that technical glitches could mean that SMS notifications warning clients about the measure would not arrive.

Last month, the Russian authorities began blocking foreign SIM cards from accessing data networks and texting services for 24 hours after entering the country to enable them to distinguish genuine foreign SIM cards from those being used to navigate Ukrainian attack drones, according to tech-specialist media outlet Rozetked.