JAKARTA, Indonesia -- Five foreigners and an Indonesian woman sentenced to death on drug charges will be executed by firing squad despite international pleas, Indonesian officials said Saturday.

A last-minute personal appeal by Brazilian President Dilma Rousseff to spare her countryman, ex-pilot Marco Moreira, and the Dutch government for its citizen, Ang Kiem Soei, "will not change or delay the execution" on Sunday, said Attorney General Office's spokesman Tony Spontana.

The men are among five foreigners and an Indonesian woman convicted on drug charges from 2000 to 2011, and sentenced to death. The executions are due to take place simultaneously in pairs, but at different locations.

Spontana said the men and two other foreign convicts -- Namaona Denis of Malawi and Nigerian Daniel Enemuo -- along with an Indonesian woman, Rani Andriani, were moved to isolation cells Saturday. Execution spots were prepared at the Nusakambangan island prison. The other woman, Tran Thi Bich Hanh of Vietnam, is due to be executed in Boyolali. Both areas are in Central Java province.

Clemency requests were rejected by President Joko Widodo in December.

"What we do is merely aimed at protecting our nation from the danger of drugs," Attorney General Muhammad Prasetyo told reporters Thursday. "There is no excuse for drug dealers, and hopefully this will have a deterrent effect."

He said that Widodo refused Rousseff's appeal by telephone to spare Moreira. The president told Rousseff that he could not commute the sentence because all judicial proceedings had followed Indonesian law and Moreira had been granted due process, Prasetyo said.

He said that the executions would not disturb Indonesia's ties with those countries.

Dutch Foreign Minister Bert Koenders told reporters Friday that Kiem Soei, who previously had his nationality declared unclear by the Indonesian government, is a Dutch citizen. He said the government in The Hague was doing all it could to prevent his execution.

"We are working on all channels -- international and to the highest level, we are trying to prevent it," Koenders told Dutch broadcaster NOS.

Koenders said the Netherlands was in contact with other countries whose nationals face execution.

Amnesty International said the planned executions would be a setback to the new Indonesian government's promise of improving respect for human rights.

Indonesia has extremely strict drug laws and often executes smugglers. More than 138 people are on death row, mostly for drug crimes. About a third of them are foreigners.