Egyptian President Abdel Fattah al-Sisi said on Tuesday he would not interfere with judicial verdicts.

Mr Sisi said Egypt's authorities would respect the independence of the judiciary.

''We will not interfere in judicial rulings,'' Mr al-Sisi said in a televised speech at a military graduation ceremony.

''We must respect judicial rulings and not criticise them even if others do not understand this.''

Fairfax Media understands the Abbott government still sees a grant of clemency by Mr al-Sisi as the likeliest avenue for Mr Greste's early release after his conviction for spreading false news and supporting the blacklisted Muslim Brotherhood.

''That's the big hope in this case,'' a source with close knowledge of the case said.

The president's willingness to intervene depends on whether he maintains the historical pro-Western tilt of his country's political elite, or whether the newer influence of Saudi Arabia wins out, the source said.

''It may be that with very effective diplomatic manoeuvres, he may shift, and grant clemency, but I suspect that he'll only do so if he firmly believes it's in the interests of Egypt.''

There was a history of Arab leaders intervening and freeing prisoners in such cases, the source added, though he stressed Mr al-Sisi appears less pro-Western than some other Egyptian leaders.

Saudi Arabia, with the support of Egypt's military, is in a regional standoff with powerful Qatar over the role of Islamist politics in the Middle East, epitomised by the Muslim Brotherhood.

Egypt's powerful military views al-Jazeera, which is based in Qatar, with deep hostility, a diplomatic source said.

Egypt might be motivated by issues such as reviving its moribund tourism industry, which was its second-highest source of income before the Arab Spring and largely comes from Western tourists.

US Secretary of State John Kerry described the tough sentences handed to Greste and his colleagues as ''chilling and draconian'' and a ''disturbing setback to Egypt's transition''.

The fact the verdict came a day after Mr Kerry visited Cairo with a view to normalising relations and resuming hundreds of millions of dollars in military aid raised questions as to whether Western influence might be strong enough to free Greste, sources said.

Australia's former ambassador to Egypt, Bob Bowker, now a Middle East expert at the Australian National University, said he had ''guarded optimism'' of Greste's early release, possibly through the conviction being overturned on appeal. ''I've believed all along that while a conviction was likely, it may prove to be politically less awkward for the Egyptians to go down that path and then quietly allow an appeal to succeed in a certain period after the initial furore has died down,'' he said.

''That's certainly easier for them in terms of managing the Saudis.''

Mr Bowker and other sources said that any threats to Egypt would be totally counterproductive. But Mr Bowker said Egypt was keen for expertise from Australian in mining and agricultural production as well as closer ties between universities.

The federal government needed to persuade Egypt's Foreign Ministry and ''other elements who are on our wavelength'' to make the case to the President and the military there would be opportunity costs involved.