CILACAP

Two convicted Australian drug smugglers have been transferred from a Bali prison to an island for execution along with other foreigners, underlining Indonesia's determination to use the death penalty despite international criticism.

The planned executions of Myuran Sukumaran, 33, and Andrew Chan, 31, have ratcheted up diplomatic tension between Australia and Indonesia following repeated pleas for mercy on their behalf.

They are among a group of up to 11 convicts, most of them foreigners, due to go before a firing squad on the prison island of Nusakambangan.

Sukumaran and Chan left Bali's Kerobokan Prison in an armoured van with a police escort and were taken to Denpasar airport for a flight to the Javanese port of Cilacap for the trip to Nusakambangan.

A Frenchman and a Brazilian are already on the island. Also facing execution are citizens of the Philippines, Ghana and Nigeria, as well as Indonesia.

Indonesian Attorney General HM Prasetyo, who had previously said all 11 would be executed, said his office would take "one or two days to analyse the legal process" undertaken by the Australian duo, but did not elaborate on what impact that would have on the executions.

He said his office was also evaluating how many would go before firing squads. All had been convicted on drug offences.

Australian Prime Minister Tony Abbott said he was "revolted by the prospect of these executions".