Ukraine has filed a complaint at the World Trade Organization (WTO) to challenge Russia over restrictions on freight transit.
"This is a yet another step taken to defend Ukraine's rights within the WTO against opaque and discriminatory restrictions by the Russian Federation," Ukraine's First Deputy Prime Minister Stepan Kubiv said in a September 15 statement.
In its complaint, seen by Reuters, Kyiv accuses Moscow of breaking WTO rules by singling out Ukraine with trade-restrictive measures -- such as requiring Ukrainian trucks to use identification seals and to move in convoy -- and by putting restrictions on Ukrainian drivers entering Russia from Belarus.
Ukraine says its trade to countries in Central and Eastern Asia and the Caucasus region had fallen by 35.1 percent in the first half of 2016 compared to the same months of 2015.
By the end of this year Ukraine will have lost about $400 million worth of exports to Kazakhstan and Kyrgyzstan, it says.
Kyiv's request for consultations marks the first step in the WTO dispute system.
The party have 60 days to resolve the dispute. After that, the WTO can create a panel of experts to review the case.