HONG KONG -- A superyacht linked to sanctioned Russian tycoon Alexey Mordashov left Hong Kong for South Africa on Thursday, nearly two weeks after the U.S. accused the city of operating as a safe haven for sanctioned individuals.

The marine department confirmed that the US$500 million superyacht Nord left Hong Kong on Thursday afternoon but did not elaborate. The private ship-tracking site MarineTraffic said it was bound for South Africa and was expected to arrive in Cape Town on Nov. 9.

The Nord arrived in Hong Kong on Oct. 5 from Vladivostok, Russia, putting the Chinese territory in the crosshairs of U.S.-China tensions.

The U.S. State Department said the presence in Hong Kong of assets belonging to sanctioned individuals called into question the "transparency of the business environment" in the city.

Hong Kong leader John Lee later said that while Hong Kong complies with United Nations sanctions, authorities "cannot do anything that has no legal basis" when it comes to sanctions unilaterally imposed by other jurisdictions. China's Foreign Ministry called the U.S. remarks "misleading."

Mordashov, who is believed to have close ties to Russian President Vladimir Putin, is one of many Russian oligarchs sanctioned by the U.S., U.K. and the European Union after Russia's invasion of Ukraine in February. He has tried to challenge the sanctions against him in European courts.

He is the main shareholder and chairman of Severstal, Russia's largest steel and mining company. Mordashov is also one of Russia's wealthiest men, with Bloomberg estimating his net worth at over US$19 billion.

U.S. and European authorities have seized more than a dozen yachts owned by sanctioned Russian tycoons to stop them from entering other ports that are unaffected by the sanctions.

Russian oligarchs have started docking their yachts at ports in places like Turkey, which has maintained diplomatic ties with Russia during the war.

The Nord, which flies a Russian flag, is 141.6 metres (465 feet) long and has two helipads, a swimming pool and 20 cabins.