Two US hikers accused Iran on Sunday of using them as ‘hostages’ in its power struggle with the West and described hearing the anguished cries of fellow inmates being beaten in Tehran's Evin prison.

Speaking at a press conference in New York hours after landing back safely on American soil following their release to Oman on Wednesday, Shane Bauer and Josh Fattal laid bare the extent of their harrowing two-year ordeal in Iran.

"We had to go on hunger strike repeatedly just to receive letters from our loved ones," said Fattal. "Many times, too many times, we heard the screams of other prisoners being beaten and there was nothing we could do to help them.

"It was clear to us from the very beginning that we were hostages. This is the most accurate term because, despite certain knowledge of our innocence, Iran has always tied our case to its political disputes with the US."

The pair, both 29, was arrested with Sarah Shourd near the mountainous border with Iraq on July 31, 2009. All three have always maintained they are innocent of spying and simply strayed across the border into Iran.

"Sarah, Josh and I have experienced a taste of the Iranian regime's brutality," said Bauer. "We have been held in almost total isolation from the world and everything we love, stripped of our rights and freedom.

"The only explanation for our prolonged detention is the 32 years of mutual hostility between America and Iran. We were convicted of espionage because we are American. It's that simple," he continued.

"The two court sessions we attended were a total sham. They were made up of ridiculous lies that depicted us as being involved in an elaborate American-Israeli conspiracy to undermine Iran."

Shourd, a teacher, writer and women's rights activist, met Bauer, a fluent Arabic-speaking freelance journalist, while helping to organize demonstrations in the US against the war in Iraq. The two moved to Damascus together in 2008.

Fattal is an environmentalist and teacher. He traveled in 2009 to Damascus. Bauer proposed to Shourd during a rare moment shared in captivity, presenting her with an engagement ring painstakingly weaved from the threads of his shirt.

Thrust into the media spotlight after three days with their families in Oman, Bauer made more political points than Fattal, who applauded the Iranian authorities for finally making the right decision about the case.

"The irony is that Sarah, Josh and I oppose US policies towards Iran which perpetuate this hostility," said Bauer.

After using the platform to urge Iran to free all "prisoners of conscience," he also criticized the US government, saying the pair's Iranian guards often defended their conditions by referencing Guantanamo Bay and CIA prisons.

"We do not believe that such human rights violations on the part of our government justify what has been done to us. Not for a moment," he said.

"However, we do believe that these actions on the part of the US provide an excuse for other governments, including the government of Iran, to act in kind."

The hikers repeated thanks to the Gulf sultanate of Oman, which posted their bail, $400,000 each, and a host of notables, from boxer Muhammad Ali to actor Sean Penn, who fought for their freedom during 781 long days in prison.

President Barack Obama described the release as ‘wonderful news’ and called Oman's Sultan Qaboos on Friday to thank him for his role in pushing Iran to free the hikers.

Their arrests angered Washington, which already has deep differences with Tehran over its controversial nuclear program, its refusal to recognize Israel and its support for militant groups in the Middle East.