Meghan Markle wore a new cross necklace in Nigeri (Image: Getty)

Meghan Markle wore a new piece of jewellery during her Nigeria trip but its origins seem to have left royal experts puzzled.

The Duchess of Sussex attended a reception for military families in Abuja where she was pictured wearing a new diamond cross necklace.

According to Page Six, the necklace was a heartfelt gift from Prince Harry to his beloved wife from his mother’s private collection.

Sources who know the couple told the outlet: “Diana remains a prominent force in Harry’s life and as a result, Meghan’s.

“So much of his work is inspired by his mum, and it’s evident how much she still means to him.

Meghan Markle visited Nigeria with Prince Harry earlier this month (Image: Getty)

“A gift to his wife that once belonged to his mother is incredibly meaningful and that isn’t lost on his wife.”

However, some people questioned the necklace’s origins, as the late princess did not appear to have worn it in public.

An insider with close ties to Diana said: “No, I didn’t recognise this at all.

“In fact, Diana was ever the professional and she generally avoided wearing religious motifs of any kind because they have the potential to offend people, so she would never usually wear such a thing.”

Princess Diana at a charity gala evening on behalf of Birthright at Garrard in 1987 (Image: Getty)

Princess Diana hugging HIV-positive children in San Paulo, Brazil, in April 1991 (Image: Getty)

Another told the outlet: “Meghan likes to curate her jewellery to tell a certain story. I find it hard to believe that she’s been sitting on this necklace for five years.”

The late Princess of Wales has only been pictured wearing a cross in public twice – in 1987 for a charity gala in London and in 1991 in Brazil.

The necklace from 1987 was auctioned to TV star Kim Kardashian last year for £160k while the 1991 one was then donated to a charity auction and later sold to an Australian collector for an undisclosed sum.