There is still hope that the imminent executions of two Australian prisoners on death row in Indonesia could be delayed after an appeal date was set for next month.

A lawyer for Myuran Sukumaran, 34, and Andrew Chan, 31, said a hearing had been scheduled at the Constitutional Court of Appeal on 12 May to hear their case.

“We keep hoping that this ongoing legal process will be respected,” Leonard Arpan added.

They were previously due to be shot dead by a firing squad in the early hours of Wednesday morning, according to a local funeral director who said he was instructed to inscribe their names and the date of death on crosses.

Prime Minister Tony Abbott and Foreign Minister Julie Bishop are considering all options – including the dramatic step of recalling Australia’s ambassador to Indonesia – in a sign of the federal government’s growing fury at the looming executions of Bali nine duo Myuran Sukumaran and Andrew Chan.

As Canberra publicly stepped up calls for clemency for the pair on Monday, Ms Bishop said she was “profoundly dismayed” at the looming executions but refused to comment publicly on what the government’s response might be.

Australia made a last-minute plea on Monday for a stay in the imminent execution of two Australian drug traffickers in Indonesia, saying reports that their trial had been tainted by corruption needed to be investigated.

The call from Foreign Minister Julie Bishop almost immediately deepened a diplomatic row with Jakarta.

Bishop said the allegations that judges requested money to commute the death sentences for the pair were “very serious” and called into question the integrity of the sentencing process.

Indonesian President Joko Widodo, speaking to reporters at Jakarta airport after returning from a regional summit in Kuala Lumpur, said such concerns should have been conveyed years ago when the case went through the courts.

Armanatha Nasir, spokesman for Indonesia’s foreign ministry, said Australians Myuran Sukumaran and Andrew Chan had been given all the legal avenues to challenge their death sentences. Australia needed to show proof of alleged corruption, he added.

The two are among nine drug convicts, including others from Brazil, Philippines, Nigeria and Indonesia, who are due to be executed by firing squad as soon as Tuesday night.