A revised manifest increased the number of people on board the Princess Ashika, which sank just before midnight on Wednesday, from 79 to 117, Tonga's police commander Chris Kelly told Radio New Zealand.

Tonga's Prime Minister Feleti Sevele has asked New Zealand and Australia to send navy divers to help recover bodies from the ferry, saying there was little chance of finding more survivors.

"The hopes for the rest are not promising unfortunately," he told journalists in Australia, where he is attending a meeting of Pacific island leaders.

"It's a very sad day... it's big for a small place. This is a huge disaster, a huge loss, we'll try and cope with it as best we can."

There were six foreigners on board including British, German, French and Japanese nationals.

Kelly said 53 people survived the tragedy but other rescue workers put the number at 55.
Two bodies have been recovered, including a British man who was carrying a New Zealand driver's licence, and most of the missing are believed to be women and children who were sleeping below decks when the ferry sank.