According to the Moscow Times, this follows a decision of the regulator Roskomnadzor to turn down its requests for a licence on new fewer than four occasions prior to the April 1 deadline.
ATR had been operating under a licence issued by the Ukrainian authorities and was seen as supporting a return of Crimea, which was annexed by Russia in 2014, to Ukraine.
Elzara Islyamova, the director of ATR, has told the RAI Novosti news agency that the station will continue to seek a licence.
Commenting on the shutdown of ATR, Denis Krivosheev, Amnesty International’s deputy director for Europe and Central Asia, said: “At the stroke of midnight, all but one Crimean Tatar language media outlets, which have come under a sustained assault since the Russian annexation, will fall silent.
“This blatant attack on freedom of expression, dressed-up as an administrative procedure, is a crude attempt to stifle independent media, gag dissenting voices, and intimidate the Crimean Tatar community.”