As Tonga prepares to formally mourn its dead, the island nation's king was facing fresh criticism for leaving the country on a four-month trip that included attending the Edinburgh Military Tattoo in Scotland.

The Tattoo was the only official engagement of King Tupou's European holiday.

The king's decision to leave the day after the Princess Ashika disaster killed 95 of his subjects, and his attendance at the Tattoo as salute-taker to military bands, has sparked calls for revolution in Tonga from democracy activists in the kingdom. It has even drawn criticism from those close to the monarch.

Mateni Tapueluelu, editor of the pro-democracy newspaper Kele'a newspaper, said yesterday he was infuriated by the reports from Scotland and expected the Tongan public to feel the same way.

"It's just going to make people angry, they're going to see the monarchy as useless and an expensive irrelevance. At best he's a waste of money," said Tapueluelu.

"When the going gets tough, he gets going: Leaving his people to swim or sink."

Tapueluelu said there was growing dissatisfaction with the Tongan, royal-dominated Government as well over its handling of the Ashika tragedy.

"I'm beginning to hear talk that we should have an interim government," he said, adding that he hoped a "peaceful transition of power is ensured".

Former All Black Va'aiga Tuigamala, now an undertaker who helped bury King Tupou's father in 2006, was reluctant to criticise the monarch but said it "doesn't look good".

Tuigamala's wife Daphne, a Tongan, lost four relatives in the Ashika sinking - an aunt and three cousins.

"The Tongan people will look to their leaders in times like these," he said, "and it would be nice if he [the king] were present."

King Tupou is not expected back in Tonga until December.

After the anguish of initially not knowing what had happened to his wife's relatives, Tuigamala said it was now certain none of the 93 people listed as missing - including at least six children under 5 - had survived.

"The longer it goes on, the worse it's going to get - the reality that their loved ones will never return will sink in. That's the hardest part," said Tuigamala.

Princess Ashika's final moments, and who's blaming who.