Indonesia on Saturday notified eight foreigners imprisoned on drug charges that they would be executed, but a Frenchman was granted a temporary reprieve after Paris stepped up pressure on Jakarta.

The eight — from Australia, Brazil, Nigeria and the Philippines — have been transported to the maximum-security prison island of Nusakambangan where they will face a firing squad, despite strident international criticism.

"My client just received a notification letter that in 72 hours there will be an execution," said Utomo Karim, the lawyer for the Nigerian convict. "There is no date specified for the execution, but families will have time to visit Nusakambangan until Tuesday 2 p.m., this could mean that it will be carried out later on Tuesday, probably in the evening or after midnight."

Andrew Chan and Myuran Sukumaran, two Australians arrested as ringleaders of the "Bali Nine" drug-smuggling group, were among those set to be executed, lawyers said. The seven other members of the “Bali Nine,” all Australian, are currently serving life sentences in Indonesian prison.

Indonesia imposes harsh punishments for drug-related crimes and resumed executions in 2013 after a five-year lull in the practice. Six executions have been carried out so far this year.

Australian Foreign Minister Julie Bishop said Indonesia had notified her government that the executions of the two Australian men would be "scheduled imminently."

"Nothing can be gained and much will be lost if these two young Australians are executed," she said in a statement, urging clemency and that legal challenges still outstanding should be heard.

Meanwhile, a temporary reprieve was granted to Serge Atlaoui, a French citizen also imprisoned on drug charges, a French embassy official said on Saturday. It was not clear why his execution was postponed.

"We remain extremely cautious. Everything can change from one day to the next," said Richard Sedillot, Atlaoui's lawyer. "I am torn between an extreme sadness to learn that other [people] condemned could be executed and the relief to learn that the man I was defending for eight years could at this stage be spared."

Marches in support of Atlaoui took place Saturday in Paris and Metz, eastern France, his hometown. France has told Indonesia the execution could damage relations, while Australia has pleaded repeatedly for clemency for Chan and Sukumaran.

"I again respectfully call on the president of Indonesia to reconsider his refusal to grant clemency. It is not too late for a change of heart," Bishop said.

Outside the maximum-security prison of Nusakambangan, an Australian diplomat and a lawyer for the two men displayed a self-portrait painted by Sukumaran to reporters. On the back was written: "The 72 hours just started."

Wire services