On December 4, 'Boris Sokolov', the world's first icebreaker tanker which transports condensate oil was, officially, launched. It was built by Guangzhou Shipyard for a major Greek shipping company.

Earlier, both of the vessels sailed through the Bering Strait and into the Chukchi Sea. The vessels voyaged through the East Siberian Sea, the Laptev Sea and into the Kara Sea.

When entering the Kara Sea, the 'Boris Davydov' voyaged to Sabetta, while the 'Boris Sokolov' proceeded towards Murmansk.

GET THE SAFETY4SEA IN YOUR INBOX!

It was the first voyage of its kind. There's thick ice in big parts of the Northern Sea Route and mostly in the eastern part of the area.

According to data from the Russian Arctic and Antarctic Institute the whole East Siberian Sea is covered by two metre one-year ice and older solid ice.

Also the Laptev Sea and the northeastern parts of the Kara Sea have thick ice layers.

Despite the ice conditions, both vessels have Arc7 ice class and break through about two metres thick ice layers.