A superyacht linked to one of Russian President Vladimir Putin's key allies has sailed through the Strait of Hormuz, despite the ongoing blockade of the critical shipping channel.

The 142m-long (465 ft) multi-deck luxury boat, named Nord, is linked to sanctioned Russian billionaire Alexei Mordashov. It travelled from Dubai to Muscat, Oman, over the weekend - one of few private vessels to transit through the strait in recent months.

Iran held high-level talks with Russia this week as its standoff with the US over the strait's re-opening continues.

Approximately one-fifth of global crude oil and liquefied natural gas (LNG) supplies normally pass through the waterway.

Mordashov, who has close ties to Putin, is not listed as the formal owner of the Russian-flagged boat. However, Nord's records indicate it was registered to a firm owned by his wife in 2022.

Nord, estimated to be worth more than $500m (£370m), left Dubai on Friday night and arrived at Al Mouj - a marina in Oman's capital - on Sunday morning, according to data on the Marine Traffic platform.

The route shown on the tracker has been used by vessels crossing with agreement from Iran.

It is not clear whether Nord gained permission from Iran to sail through the route.

Mordashov made his fortune largely through his steel and mining company Severstal - the largest such firm in Russia.

With an estimated net worth of about $37bn (£27bn), he is the richest Russian national listed by the US business magazine Forbes.

Iran has severely restricted shipping through the Strait of Hormuz in response to US and Israeli strikes that began on 28 February.

Earlier this month, Tehran warned that any vessel that approaches the strait would be targeted.

The US then announced that its forces would intercept or turn back vessels travelling to or from Iran's ports.

The Nord route shown by Marine Traffic does not indicate the yacht stopped in Iran.

The United States Central Command (Centcom) defines the blockade starting point as further east of the vessel's last reported location.

Maritime traffic through the Gulf channel is currently at a fraction of pre-war levels.

The conflict has contributed to a sharp rise in global oil prices, with the global benchmark Brent crude rising to $109 (£80) a barrel on Monday.

The Nord has a swimming pool, submarine and helipad, according to a profile in the magazine Superyacht Times.

Mordashov has been targeted by Western sanctions, including from the UK, US and European Union since Russia launched a full-scale invasion of Ukraine in 2022.

Hong Kong and the Maldives have previously not seized Nord despite calls from western nations to freeze his assets.

In March 2022, one of Mordashov's smaller boats, the 65m (215ft) Lady M, was impounded by Italian police in the port of Imperia.

Several Russian oligarchs' boats have been seized or denied entry to European ports under the sanctions related to the ongoing Russian invasion of Ukraine.

That has prompted the movement of such boats to areas around the world considered beyond the reach of the sanctions, including ports in the Middle East and Asia.

While long-term peace negotiations stall with the US, Tehran has this week focused its diplomatic efforts on cementing its relationship with its ally Russia.

Putin hosted an Iranian delegation in St Petersburg on Monday, where Iranian Foreign Minister Abbas Araghchi hailed their "strategic relationship".

The Russian president told Araghchi that the Iranian people were "courageously fighting" for their sovereignty in the face of American and Israeli pressure, Russian state-run news agency Tass reported.

Araghchi shared photos on X showing him smiling and shaking hands with Putin and his Russian counterpart Sergei Lavrov.

He wrote: "Recent events have evidenced the depth and strength of our strategic partnership.

"As our relationship continues to grow, we are grateful for solidarity and welcome Russia's support for diplomacy."

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