Prince Harry and his wife Meghan Markle piled fresh criticism on the British royal family in new episodes of their Netflix documentary series released on Thursday, accusing their aides of being part of media attacks.

In the first tranche of episodes released last week, Harry and Meghan launched fierce attacks on the media over their treatment, some of which they said had been racist, but the royals themselves escaped relatively unscathed.

However, there was greater criticism of his relatives and their aides in the final three episodes, accusing them of not just failing to prevent negative coverage in the press, but actively encouraging it.

"It was already clear to the media that the palace wouldn't protect her. Once that happens, the floodgates open," Harry said.

The couple were also shown talking about a former senior aide to his elder brother Prince William, the heir to the throne, who provided evidence in a legal action Meghan had brought against the Mail on Sunday newspaper that had published a letter she had written to her estranged father.

"It's your brother. Not going to say anything about your brother, but it's so obvious," Meghan said.

In his evidence, the former aide, Jason Knauf, suggested Meghan had been aware at the time that the letter could leak.

"That's why I'm now living in a different country because all the comms (communications) teams basically like try to outdo each other," Harry said. "But this is the contract, the symbiotic relationship between the two institutions working the best they can."

Netflix included a statement from a representative for Knauf, which said the claims were "entirely false".

The episodes were released just hours before King Charles, his wife Camilla, William and his wife Kate along with other royals will attend a carol service at London's Westminster Abbey to "recognise the selfless efforts of individuals, families and communities across the UK".

- Reuters