A Russian billionaire has had his £340m ($425m) superyacht – one of the world's biggest – impounded by authorities in Gibraltar after a German shipbuilder claims it is still owed £13m in fees.

Andrey Melnichenko's world-famous "Sailing Yacht A" has been stuck in the British territory since Wednesday (15 February).

The Bermuda-registered vessel – measuring higher than Big Ben's tower at 100m, and 143m long – was built by Nobiskrug and left the Kiel shipyard in north Germany two weeks ago.

It was seen sailing to the south of Spain earlier this month where it had been expected to undergo further sea trials, before being delivered to Melnichenko.

But a top Gibraltar court official, Admiralty Marshal Liam Yeats, told the BBC on Monday (20 February): "The vessel is under arrest and is currently at anchor in British Gibraltar Territorial Waters."

According to documents seen by Germany's NDR news, Nobiskrug is demanding an outstanding payment of €9.8m, as well as €5.5m for subcontractors and interest charges.

A spokesman for Melnichenko, 44, who has an estimated net worth of $13.2bn, described it as "a technical problem".

He said: "We are confident that the arrest will be removed within a few days and this unpleasant episode will be over. "

Andrey Melnichenko
Russian billionaire Andrey Melnichenko Reuters

The Gibraltar Port Authority said it puts security guards on board any vessels "to protect the vessel and its contents".

Designed by Frenchman Philippe Starck, the three-masted superyacht boasts eight decks, connected by multiple lifts, and an underwater observation room. It is designed to accommodate 20 guests and a crew of 54, and has a top speed of 21 knots.

Melnichenko, an industrialist with large holdings in coal, energy and fertiliser sectors, made headlines in September last year when he moored his other £225m sea vessel – named "Motor Yacht A" – next to HMS Belfast on the River Thames.

At 119m long, it casts a smaller shadow than Sailing Yacht A but still features three swimming pools, including one with a glass floor.

Melnichenko, whose wife Aleksandra is a former model from Serbia, is said to favour using the letter "A" for the name of his vessels so they appear first in shipping registers.

motor yacht a
Andrey Melnichenko's other sea vessel, named Motor Yacht A, was moored next to HMS Belfast on the River Thames in September last year Reuters