Below is an excerpt from: http://www.fni.no/doc&pdf/FNI-R0405.pdf

Fee practice. Related to ARCOP and this initial phase of harmonisation under GATS/EU requirements for treatment-no-less favourable and equal competition, there may be a problem concerning 'fees for services rendered'. As set forth in Article 8.4. of the 1990 Rules, there may be questionable compliance with the requirement of non-discrimination.
This requires vessels navigating the NSR to pay for services rendered by the Marine Operation Headquarters and the Northern Sea Route Administration (NSRA) in accordance with the adopted rates. In practice it seems improbable that the current Russian fee rate, $3.33–$73.02 per ton depending upon cargo, is required of Russian vessels. 6 The fees, if justified under Article 234, must apply to all vessels, and the likely
Russian practice on this point is contrary. There may exist other special Russian domestic requirements as well.