Hong Kong has said it will not seize the superyacht of a Russian oligarch who is under Western sanctions. Chief executive John Lee said Hong Kong would be accountable to United Nations sanctions but not "unilateral" ones imposed by "individual jurisdictions". The $521m (£472m) boat belongs to Alexei Mordashov, an ally of Russia"s President Vladimir Putin and one of the country"s richest men. His yacht arrived in Hong Kong last week after sailing from Russia. But Mordashov is not believed to be on it. The billionaire was sanctioned by the US, the UK and the EU after Russia invaded Ukraine earlier this year. But Hong Kong"s government said it was not bound by those sanctions. For close to a week now, the multi-storey Nord superyacht has been a conspicuous sight in the city"s Victoria Harbor with the Russian flag flying at its mast. "We will comply with United Nations sanctions, that is our system, that is our rule of law," said Lee, who has himself been sanctioned by the US for his role in implementing Hong Kong"s repressive national security law. The US, EU and UK have sanctioned hundreds of Russians and their businesses. China, however, has remained a Russian ally and has so far not condemned Moscow"s decision to invade Ukraine. "Hong Kong"s reputation as a financial center depends on adherence to international laws and standards," a US State Department spokesman said. "The possible use of Hong Kong as a safe haven by individuals evading sanctions from multiple jurisdictions further calls into question the transparency of the business environment." It"s unclear how long the superyacht will remain in Hong Kong"s waters. Mordashov"s spokesman told Bloomberg News the steel tycoon was in Moscow. Prior to the war in Ukraine, he was Russia"s richest man, according to Forbes, with a $29.1 billion fortune built through his steel and mining company Severstal. The Nord is believed to be his biggest yacht asset. The 465-foot (141m) yacht is larger than a football field and is described as one of the world"s most extravagant boats, according to Forbes. The billionaire had already lost one of his smaller boats, the 215ft Lady M, to Western sanctions in March after it was seized by Italian police in the port of Imperia. Several Russian oligarchs" boats have been seized or denied entry to European ports this year under Western sanctions related to the war in Ukraine. That"s prompted the movement of such boats to areas around the world considered beyond the reach of Western sanctions- including ports around Asia, Turkey and the Caribbean. — BBC