Apex domains cannot have CNAME records.
Question and response
Question
dig mtw.RU. NS
Answer
mtw.ru. 5 NS ns1.mtw.ru.
mtw.ru. 5 NS ns.mtw.ru.
Authority
The response has no authority records.
Additional
ns.mtw.RU. 5 A 93.95.102.170
ns1.mtw.RU. 5 A 93.95.100.24
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0