Meghan Markle has been accused of trying to upstage Kate Middleton by soft-launching her lifestyle brand's new products right before the Princess of Wales made her highly anticipated return to public duties over the weekend.

On Saturday, Middleton made her first official public appearance since announcing her cancer diagnosis and treatment at King Charles III's birthday parade, Trooping the Colour.

But just hours before the event, Markle and Prince Harry's friend Nacho Figueras unveiled on social media a new jam and dog biscuits from the Duchess of Sussex's American Riviera Orchard label.

The move was criticized by royal expert Jonathan Sacerdoti, who suggested on "TMZ Live" Monday that Markle may have tried to "steal the thunder" of Middleton and the British royal family.

Royal Family
(From L) Britain's Prince George of Wales, Britain's Prince Louis of Wales, Britain's Prince William, Prince of Wales, Britain's Princess Charlotte of Wales, Britain's Catherine, Princess of Wales, Britain's King Charles III and Britain's Queen Camilla stand on the balcony of Buckingham Palace after attending the King's Birthday Parade, "Trooping the Colour", in London, on June 15, 2024.
(Photo : JUSTIN TALLIS/AFP via Getty Images)

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"It was predicted [Meghan and Harry] might try and do something to steal the thunder of the royal family. It's the King's official birthday. He's also been unwell [and] undergoing cancer treatment," Sacerdoti said.

"And sure enough, there was a revelation that Meghan Markle, with her business, American Orchard Riviera...released a new jam and some dog biscuits to coincide with this appearance of Catherine and the King," he added.

The royal commentator continued to take digs at Markle, saying that if the former "Suits" star did intend to try to steal the spotlight from Princess Kate, it was a "pathetic" attempt at best.

Sacerdoti also poked fun at the name of Markle's company, describing it as a "word salad that tried to indicate classiness."

Meghan Markle, Duchess of Sussex
Meghan, Duchess of Sussex, looks on as she attends a Sit Out with Britain's Prince Harry (unseen), Duke of Sussex, at the Nigerian Defence Headquarters in Abuja on May 11, 2024 as they visit Nigeria as part of celebrations of Invictus Games anniversary.
(Photo : Kola Sulaimon/AFP via Getty Images)

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When "TMZ Live's" hosts pointed out that it could be just a "coincidence" on timing, Sacerdoti acknowledged that "it could be."

However, the royal expert claimed that the British public was now "very fed" with Markle, Prince Harry, and their "antics" following their bombshell allegations against the royal family in interviews and projects over the years.

Sacerdoti added that the Trooping the Colour and Princess Kate's appearance "showed really what the royal family is about."

"It was wonderful to see Catherine back with the kids, with the family," Sacerdoti said. "Britain was really pleased to see her there. The world was really pleased to her there, and that's the princess that everybody was looking at this weekend."

Royal Family
Britain's King Charles III (R) looks at (L-2ndR) Britain's Prince George of Wales, Britain's Prince William, Prince of Wales, Britain's Prince Louis of Wales, Britain's Princess Charlotte of Wales, and Britain's Catherine, Princess of Wales, as they wave on the balcony of Buckingham Palace after attending the King's Birthday Parade "Trooping the Colour" in London on June 15, 2024.
(Photo : HENRY NICHOLLS/AFP via Getty Images)

Before Saturday's parade, the last royal engagement Middleton attended was back in December last year when she joined the royal family on their annual walk to church on Christmas Day.

There had been few updates on Middleton's health since she released a video message in March announcing that she had been diagnosed with an unspecified form of cancer and was undergoing preventative chemotherapy.

However, Middleton surprised royal fans Friday when she revealed that she would be attending Trooping the Colour the next day.

"I'm looking forward to attending the King's Birthday Parade this weekend with my family and hope to join a few public engagements over the summer, but equally knowing I am not out of the woods yet," the Princess of Wales wrote in a personal letter.

Kate Middleton Catherine, Princess of Wales
Britain's Catherine, Princess of Wales, smiles inside the Glass State Coach on her way to Horse Guards Parade for the King's Birthday Parade "Trooping the Colour" in London on June 15, 2024.
(Photo : Henry Nicholls/AFP via Getty Images)

On Saturday, Middleton looked radiant in a white Jenny Packham dress and matching hat by Philip Treacy when she stepped out with her three kids, Prince George, Princess Charlotte, and Prince Louis, to attend the King's birthday parade.

Markle and Prince Harry have not attended Trooping the Colour since his father Charles became King.

The couple stepped back from their roles as working royals and left the U.K. in 2020.