Australians have been warned by their government to avoid travelling to Sabah after "credible" reports that terrorists are planning to kidnap foreigners.

"Australians are advised to avoid all travel to coastal resorts, islands and dive sites off the east coast of Sabah" on Borneo island, the foreign affairs department said in a travel advisory issued late Wednesday.

"We have received credible reports that terrorists are planning kidnapping attacks targeting resorts frequented by foreigners."

Militants have in the past kidnapped foreigners from the eastern part of mainland Sabah, and from islands and sea off its east coast, the department said.

Risk remains

The travel warning also urged Australians to exercise a high degree of caution throughout Malaysia as "the risk of terrorist attack against Western interests in Malaysia remains".

It said travellers should take care particularly in commercial and public areas known to be frequented by foreigners such as hotels, clubs, restaurants, bars, schools, marketplaces, places of worship, outdoor recreation events and tourist areas.