An earthquake measuring 6.6 on the Richter scale struck off eastern Indonesia today, the Indonesian geophysics agency said.

The quake occurred at 9.17am local time (8.17am in Malaysia) and its epicentre was 184km north-east of Maluku Barat Daya on the Molucca islands, the agency said.

The quake occurred at a depth of 173km and there were no immediate reports of damage, it added.

"There was no panic," said Sutopo Nugroho, a spokesperson for the National Disaster Management Agency, adding that no damage was expected, considering the quake's depth.

The quake was also felt on the Australian mainland in the city of Darwin and surrounding areas, according to local newspaper NT News.

Bureau of Meteorology senior forecaster Chris Kent told the paper that the "significant" quake lasted several minutes.

"We're on the third floor and it gave us a shake," Kent said.

The Joint Australian Tsunami Warning Centre said there was no tsunami threat to the Australian mainland, islands or territories from the quake.

Indonesia sits on the Pacific Ring of Fire, an area known for seismic upheavals and volcanic eruptions.

- dpa