The St. Petersburg-based ship maker said the 50 Years of Victory icebreaker has been towed along the narrow Neva Riva to the St. Petersburg seaport and will undergo a series of tests to check its manoeuvrability and speed performance in the open sea.

"Experts will also test the ship’s navigation and communications systems, water-purification and anti-freezing equipment and other devices, whose performance cannot be checked near shore," the company’s press service said.

An upgrade of the Arktika-class icebreaker, the 159-meter (522-foot) long and 30-meter (100-foot) wide vessel, with deadweight of 25,000 metric tons, is designed to break through ice up to 2.8 meters deep (9.2 feet). It has a 138-man crew.

The Russian nuclear-powered icebreaker fleet, which is operated by the Murmansk Shipping Company, currently consists of five Arktika-class icebreakers (Arktika, Sibir, Rossiya, Sovetskiy Soyuz, and Yamal), and two Taymyr-class river icebreakers (Taymyr and Vaygach).

The icebreaker was launched in 1989 but could not be completed before 2006 due to the poor state financing.