The daughter of a man killed by Islamic State militants has expressed anger at complaints by his alleged killers that they will not get a fair trial.
Bethany Haines, whose father David died in Syria, said Alexanda Kotey and El Shafee Elsheikh had shown "no remorse".
The pair, who say their UK citizenship has been illegally withdrawn, allegedly belonged to an IS group dubbed "The Beatles" because of their UK accents.
Now jailed in Syria, they called the murder of IS hostages "regrettable".
Ms Haines, whose father was held hostage for 18 months by the group, said: "It shocks me that two individuals who have committed such heinous crimes have been treated like guests with access to the media and are allowed access to smartphones.
"As for them saying that their actions in Syria are regrettable is an understatement."
In an interview with Associated Press from northern Syria, Elsheikh said the "illegal" withdrawal of their UK citizenship put them at risk of "rendition and torture".
"Being taken to any foreign land and treated in any way and having nobody to vouch for you," he said.
"When you have these two guys who don't even have any citizenship... if we just disappear one day, where is my mum going to go and say, 'Where is my son?'"
He said he could have "no fair trial" when he was "the Beatle" in the media.
UK security minister Ben Wallace said the government had always been clear that people who went to fight for terrorist groups overseas would face prosecution. He said Britain would work with its international allies to make sure terrorist suspects who were detained were brought to justice wherever was most appropriate.
Ms Haines questioned whether the men could ask for their rights when they had "stripped" her father of his by holding him "with his family not knowing whether he was dead or alive".
She said: "In my opinion they should be given an orange jumpsuit and stripped of all the things they hold dear and left to rot in Guantanamo Bay."
Her views were echoed by Diane Foley, whose son James, an American journalist, was beheaded by the group in Syria in 2014. She said she wasn't interested in their opinions and doubted the sincerity of what they had said.
"I am interested in them being held accountable for their horrific crimes and right now, they look like they're on vacation," she told Radio 4's Today programme.
"I know it's complicated but if someone doesn't take the leadership and take them to trial I fear they'll get away."
Sarah El Deeb, the journalist who interview the pair, described the men as "very smart" and "very religious".
"I don't think they were very apologetic about being members of Islamic state," she told the BBC.
Murder of hostages
US officials believe the so-called "Beatles" cell beheaded more than 27 Western hostages and tortured many more.
Kotey told the Associated Press that he "didn't see any benefit" to the killings.
"It was something that was regrettable," he said.
He also said many people in IS would have opposed the murders "on the grounds that there is probably more benefit in them being political prisoners".
The other cell members were Mohammed Emwazi, nicknamed "Jihadi John", and Aine Davis.
All four were from west London.
Emwazi, who was the alleged ringleader and appeared in videos showing hostages being beheaded, was killed by a drone strike in 2015.
Davis was convicted of being a senior IS member and was jailed in Turkey last year.
Captives killed by the cell are thought to have included Alan Henning as well as Mr Haines. The men, both British aid workers were beheaded.
Last month, Home Secretary Amber Rudd said the two remaining suspects in the 'Beatles' gang should go on trial.
She said the US and UK were in talks about what to do with the two men.
Both Kotey and Elsheikh have been designated terrorists by the US, which says they used "exceptionally cruel" torture methods.
UK defence minister Tobias Ellwood said he believed the men should be tried in an international criminal court.
The families of some of the victims also said the pair "should face trial".