He's been called Prince Harry's 'real brother', but who is Ignacio 'Nacho' Figueras?

Prince Harry has visited Tokyo with his close friend, Ignacio 'Nacho' Figueras.

The pair are in Japan for the ISPS Sports Values Summit. The organisation ISPS Handa works to highlight the transformative and community building powers of sport.

The two friends are next set to visit Singapore, where they will each head up a team in the Sentebale ISPS Handa Polo Cup.

During their Tokyo stayover, Figueras – a longstanding friend of the duke's – posted a photo on Instagram, captioned "shopping for our wives" with the pair posing in sunglasses.

He went on to thank "Tokyo for your generous hospitality and kindness towards us. And of course, for your continued support of Sentebale."

Many fans were quick to comment on the seemingly close bond between the friends, with some calling Figueras Harry's "real brother" in light of his current estrangement from Prince William and much of the rest of the Royal Family.

Who is Nacho Figueras?

Ignacio 'Nacho' Figueras, 46, is an Argentinian polo player. Raised in Beunos Aires, he reportedly began playing polo aged nine and turned professional at 17.

He is reported to have met his wife, Deflina Blaquier – the daughter of a polo player – at a match in 1997. The pair married in 2005, five years after welcoming their first child Hilario.

They went on to have three more children: Aurora, Artemo and Alba.

In 2000, he began modelling for Ralph Lauren as the face of their fragrances. He has also put his name and likeness to a series of ghost-written romance books.

How do Harry and Meghan know Figueras?

Prince Harry and Figueras reportedly met in 2007 at a polo match and became close friends.

Figueras was mentioned in the acknowledgements of Harry's memoir Spare for his "unwavering friendship and support" – alongside other famous names including Tyler Perry and James Corden.

The polo professional was one of Harry and Meghan's friends who took part in their eponymous six-part Netflix documentary series.

He discussed when Harry told him about Meghan shortly after the couple had been on their first date.

"He looked at us and said, 'Guys, I met a girl, we've just met but I think this might be the one.'"

Figueras added: "You could tell right away that those eyes were those of someone who'd fallen in love."

Harry has been defended publicly by Figueras on several occasions, most recently when the model replied "BS" on Twitter to a Page Six report that the Sussexes marriage is on the rocks.

Figueras has worked with Harry on projects for the duke's charity Sentebale many times, and spoke about Harry's commitment to his philanthropic work in an interview he gave to People magazine last year.

"From day one, I saw how committed he was to his charity. Fast forward 15 years, I've been to Lesotho with him a few times, and I've seen what great work the charity does and how important it is for a lot of kids, how committed he is, how much he really cares about it."

Sentebale was founded in 2006 jointly with Prince Seeiso of Lesotho in memory of the two mens' mothers, both of whom had died. The name means 'Forget-me-not' in Sesotho – which were the late Princess Diana's favourite flowers – and the charity works to address the basic needs of young people and children in Lesotho, as well as tackling the root causes of poverty and inequality.

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