Two Australian members of the "Bali Nine" drug trafficking ring, arrested in Bali in 2005 for attempting to smuggle 8 kg (18 lb) of heroin to Australia, will be executed this month, a government official said on Friday, ignoring clemency pleas from their home country.

Myuran Sukumaran and Andrew Chan are among eight prisoners due to be executed as President Joko Widodo pursues a hardline approach to drug offences, drawing criticism from rights activists at home and abroad.

"We received notification from Bali's attorney general yesterday that the two Australians whose clemency has been rejected by the president will be executed in February 2015," said Foreign Ministry spokesman Armanatha Nasir.

"We have informed the Australian embassy of this."