Thomas Markle Snr has revealed he is aiming to take legal action in the US in order to see Archie and Lilibet.
During an interview with Fox News, Meghan Markle's father, who lives in Mexico, spoke about the ongoing rift between him and his daughter.
"I will be petitioning the California courts for the rights to see my grandchildren in the very near future," he said.
In the clip, filmed at his home, he also asked for Lili to be christened at the Queen's church.
"We shouldn’t be punishing [Lili] for Meghan and Harry’s bad behaviour.
"Archie and Lili are small children. They’re not politics. They’re not pawns. They’re not part of the game. And they’re also royal and entitled to the same rights as any other royal."
He then says he hopes the Queen, and "the people of England will stop and think about this", adding "Archie and Lili are just sweet little kids, let keep it to that".
Markle Snr previously revealed that he intends to do interviews every 30 days until his daughter responds to him, as the pair have not spoken for more than three years.
It comes after the news that Meghan's estranged half-brother, Thomas Markle Jr. is reportedly set appear on Big Brother Australia VIP, after he was spotted arriving in Sydney Airport.
According to the Daily Mail, the Washington-based window fitter was whisked away into hotel quarantine in Sydney, just days after Katie Hopkins was booted from Australia after she tried to break quarantine rules.
Caitlyn Jenner, who is currently running for Governor of California, is also reported to be appearing on the show.
Thomas Jr is not believed to have seen or spoken to his half-sister since the 2000s, but that hasn’t stopped him from taking part in several scathing interviews since she joined the royal family.
In May 2018, just before Meghan Markle walked down the aisle to marry Prince Harry, Thomas Markle Jr. penned an open letter to his half sister which was published by In Touch.
“With all the memories of watching you grow up, it’s hurtful that you would forget about us,” he wrote.
“It does hurt my feelings not getting invited to your wedding, along with the rest of the family.
“But it’s not too late to send me an invite along with your entire family.”
Additional reporting by Rebecca Taylor.
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