This is said in the statement of the U.S. Department of State.
"We call on the Russian Federation to reverse the Ministry of Justice’s recent decision to designate the Crimean Tatar Mejlis as an ‘extremist’ organization and the decision by de facto authorities in Crimea to suspend this democratic institution," the Assistant Secretary and Department Spokesperson, Bureau of Public Affairs, John Kirby, stated.
Kirby noted that the Mejlis had long been a representative body for the traditionally under-represented and historically oppressed Crimean Tatar population. He added that it had also served as an important independent voice in preserving their culture and protecting them from discrimination.
"Russian authorities have no basis or jurisdiction to assert Russian law over Tatar conduct in Ukraine. A ban on the Mejlis would prohibit it from convening, publishing its views in mass media, or holding public events, which contravenes basic democratic principles," reads the statement.
The United States again called on Russia to end its occupation of Crimea and return control over this piece of Ukrainian territory. “Sanctions related to Crimea will remain in place as long as the occupation continues,” the statement says.