The parents of Australian Al Jazeera journalist Peter Greste have visited their son in jail for the first time since his arrest by Egyptian authorities, calling it a “horrendous experience”.

Juris Greste and wife Lois made an emotional visit to Cairo after the 48-year-old was sentenced in late June to seven years for aiding the blacklisted Muslim Brotherhood and “spreading false news”.

“It was a horrendous experience,” Juris Greste told the Australian Broadcasting Corporation of the 45-minute meeting on Wednesday.

“Had we had a small bucket between us as we were sharing hugs, it might have even overflowed ... with tears and sobs.”

Greste’s colleague, Egyptian-Canadian Mohamed Fahmy, was sentenced to the same term while their producer Baher Mohamed was handed 10 years in a decision that sparked global outrage and fears about press freedoms.

Lois Greste said her son, who was “very sombre”, had been moved to a different prison where he was being kept in a “dormitory-like situation” with about nine others.

“I think it was probably one of the most difficult days of my life,” she said of the visit.

“We gave him a hug when we saw him, and also when we left.”

Greste and his parents discussed their legal options, but Juris Greste admitted they were preparing themselves for the “cold, hard, real possibility” their son could serve his full sentence.

“A member of my family spent seven years in a Soviet gulag, and returned, and when we met them in Riga, they almost took my breath away how sane and how still full of life they were,” Juris Greste said.

“So all these things are possible, but nevertheless, just the very thought of looking ahead is very sobering and almost depressing.”

Australia and the United States are leading calls for President Abdel Fattah al-Sisi to pardon the journalists, although the new Egyptian leader has said authorities will not interfere with the justice system.

The Al Jazeera ruling is the latest issue in Egypt to stoke concern among rights groups since a 2011 uprising toppled long-time autocrat Hosni Mubarak.

Since the army ousted Islamist president Mohamed Mursi in July 2013, political unrest has reached unprecedented levels in Egypt, with more than 1,400 people killed and at least 15,000 jailed in a government crackdown.