Canberra's National Portrait Gallery has taken down an image of Indonesian President Joko Widodo following the execution of two Australian drug smugglers, saying it feared for the artwork's safety.

Andrew Chan, 31, and Myuran Sukumaran, 34, were shot by firing squad in Indonesia on Wednesday over their role in the so-called "Bali Nine" heroin smuggling ring.

The executions of the two Australians, along with five other foreigners and one Indonesian, went ahead despite international criticism and calls for mercy from Canberra.

National Portrait Gallery director Angus Trumble said in a statement late Thursday he had removed the photographic portrait of Widodo given the strength of feeling about the executions.

"My feeling yesterday, on Wednesday morning, was that in view of the circumstances and our operations, and my best assessment of the risk of damage to the work of art, it was necessary to remove it from public display," he said in a statement.

"Also, I was swayed by the statements of both the prime minister and the leader of the opposition and of course the position of the parliament and the recall of our ambassador."

Prime Minister Tony Abbott said Australia deplored the killing of the men which he said was "both cruel and unnecessary", and recalled its ambassador to Indonesia.

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Trumble said the removal of the image was a "temporary measure" and there had been no incidents relating to the work.

"My primary responsibility is the care of the works in our collection and the safety of our visitors," he said.

Trumble said he respectfully disagreed with the views of the artist who created the portrait, Adam Ferguson, "who feels the work should remain on display".

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