Lawyers for Bali Nine pair Andrew Chan and Myuran Sukumaran have presented new evidence in administrative court. The Australians’ legal team will return to the Jakarta court with an expert witness to help them with their case.

Chan and Sukumaran’s lawyers filed an appeal in the administrative court in February, challenging Indonesian President Joko Widodo’s blanket ban on clemency that affected 64 death row inmates. The Bali Nine duo’s lawyers argued that the president did not review individual cases on their merits as required by law, adding the leader failed to follow the due process by denying all the appeals at once.

The administrative court rejected their application, saying that it did not have jurisdiction to hear the case. The lawyers have then filed an appeal. And on Wednesday, lawyer Leonard Arpan revealed that they have presented new evidence on laws on the president’s prerogative rights to the Jakarta court. They will return to court with an expert witness on Monday.

It is expected that the witness will give evidence relating to the dismissal of the appeal. If not, Rusdihadi Teguh, a lawyer for the state, told reporters that they would object.

Chan and Sukumaran were transferred from the Kerobokan prison to Nusakambangan Island earlier in March in preparation for their execution. However, they may have to wait for months before the grim event. The Supreme Court has decided to review the case of Mary Jane Fiesta Veloso, a Philippine national set to be executed alongside Chan and Sukumaran, and the entire proceeding may take around three months to complete.

Attorney-General spokesman Tony Spontana said that they would wait for all legal procedures to be over before they would proceed with the execution. Simultaneous executions are believed to be “more efficient and effective.” With Veloso’s case under review, the Bali Nine pair, as well as the other seven death row convicts who would face the firing squad with them, have been given more time. Chan and Sukumaran remain in Nusakambangan Island as they wait for all their legal avenues to be exhausted.

Meanwhile, Mr Widodo is too busy to take Australian Prime Minister Tony Abbott’s call about the Bali Nine pair in death row. The Asian country’s envoy in Australia, Nadjib Riphat Kesoema, said on Thursday that the Indonesian leader had not talked to his Australian counterpart ever since their initial phone call.

“The second and the third time – the President was so busy,” Kesoema said in Canberra. He added that the president’s first program is to visit his people in the provinces.