Operators must hold the correct licence in order to legally offer gambling in Lithuania, with those running in the country without approval being regarded as illegal operators.
Gambling laws in the country permit the Control Authority to take action against unlicensed operators, including blocking access to their websites in the country.
Any operator that is blocked is also added to the Control Authority’s blacklist of unlicensed and illegal operators, which is updated regularly on its website.
The only way an operator can be taken off the blacklist is if it secures the relevant licence to offer online gambling in Lithuania.
“The Control Authority strongly recommends all online gambling operators review all their activities related to remote gambling in Lithuania and take actions to ensure that such services are not available for Lithuanian customers,” the Control Authority said.
“After having identified the fact of illegal remote gambling activity in the Republic of Lithuania, the Control Authority is authorised to take measures established in the Gaming Law.”
The warning comes after the Gambling Supervisory Authority last month imposed its first ever fine against an operator. UAB Tete-a-Tete Casino, operator of the CBet brand, was told to pay €15,000 (£13,049/$18,145) for unreasonably setting betting limits on an online customer.
Also last month, the Gambling Supervisory Authority fined an employee of a digital media business for placing illegal gambling advertisements on basketball news and information website Krepšinis.net.
The site was found to be hosting gambling ads with slogans and animated backgrounds, and featuring promotional bonuses, which are prohibited under Lithuanian regulations. The ads also lacked the mandatory warnings required in gambling adverts.