The largest Ukrainian mobile operator Kyivstar, after a large-scale outage, at 20:00 on Monday, partially restored the work of fixed-line communication services; the company promised to complete the work on restoring other services during the day on December 13.

"As of 20:00 on December 12, the work of fixed-line communication services has been partially restored. Now, the company's specialists are working to restore other services and are doing everything possible to fully complete this work on December 13, 2023. The restoration of services can occur gradually, and we will inform about it additionally," the Kyivstar press service said in a statement.

Kyivstar called the attack on the company on Monday "the largest hacker attack in the history of the global telecom market." They also assured that the company's specialists began resuming services without delay.

Kyivstar expressed gratitude to law enforcement agencies, government services, and the Security Service of Ukraine for their immediate response and professional assistance in resolving the unprecedented situation.

Also, on behalf of the entire Kyivstar team, the company thanked customers, colleagues in the telecom market, and corporate clients for their understanding and support.

The company assured that after stabilization of the network, all subscribers and corporate clients for whom Kyivstar services were unavailable after the hacker attack will definitely receive compensation.