Tonga's ability to communicate with the rest of the world has severely been restricted after a submarine cable broke, cutting off the Pacific island kingdom from almost all mobile phone and Internet services.

The country, which consists of some 170 islands divided into three main island groups and has a population of 110,000, relies heavily on international links for daily supplies and vital tourist earnings.

"We are all heavily tied to the Internet for doing business and for the government," Mary Fonua, editor of the online news service Matangi Tonga, told AFP news agency on Wednesday.

"There's no Facebook, which is how the Tongan diaspora communicate with each other, businesses can't get orders out, airlines can't take bookings for passengers or freight."

While the authorities look into the cause and struggle to find a solution to the disruption, which began on Sunday, they have turned to a small, locally operated satellite connection as back-up.

180221105901986

In the meantime, non-essential social media sites such as Facebook have been blocked to preserve much-needed bandwidth.

The restricted access also meant serious problems getting money transfers through for families who rely on income from relatives working overseas.

"It's an absolute disaster for Tonga, a national crisis," Fonua said.

Tonga Cable, which administers the 827km cable between Tonga and Fiji, said Internet traffic had to be prioritised until repairs were completed, and in the meantime, social media websites may be blocked while the country relies on makeshift connectivity.

"Eighty percent of our international traffic is from social media," Tonga Cable Director Paula Piukala told Radio New Zealand.

"We may block Facebook, YouTube and stuff like that in the meantime so that we can maximise the small bandwidth that we have from satellite on what is important to the country."

At the Bank of South Pacific Tonga, acting operations manager Salesi Fineangano said telex transfers could be completed via satellite connection to the bank headquarters in Papua New Guinea, "but we need the regular internet connection for Moneygram, internet banking and emails."

Officials said it could take up to two weeks to fix the problem.