"I am deeply saddened by the news of the earthquake, which has caused heavy loss of life, numerous injuries, and damage to public and private buildings in your country," read the message to Indonesia's President Susilo Bambang Yudhoyono.

"I share your grief over this tragic incident and would like to express my heartfelt condolences to the bereaved families and wish the injured speedy recovery and the affected area early reconstruction."

The death toll from Saturday's 6.3-magnitude quake stands at about 4,300 while some 200,000 people were displaced.

Meanwhile, caretaker Prime Minister Thaksin Shinawatra will send condolences to Indonesia, said government spokesman Surapong Suebwonglee.

Thailand will ship 1,000 tonnes of rice to help people affected by the earthquake.

"The country will also donate Bt4 million to Indonesia," he said.

Caretaker Foreign Minister Kantathi Suphamongkhon said four Thai students in Yogyakarta were slightly injured in the earthquake.

He said Thailand was preparing to send doctors as well as other relief assistance to the victims of the quake. The minister was speaking from Kuala Lumpur where he is attending the Non-Aligned Movement Ministerial Meeting.