If you want to set up DNS servers having names in .ru domain for .com domain

If you delegate gTLD or non-Russian ccTLD domain name with DNS servers in RU TLD, they shall be activated in NSI-registry by the current gTLD or non-Russian ccTLD registrant.

In no manner NSI-registry base is employed by RU domain, thus no registrar in RU TLD may activate DNS servers in this TLD in NSI-registry base. This is done by the corresponding registrar or COM domains (or other TLDs employing NSI-registry), activating DNS servers in the corresponding registry as "external hosts".