Two British Iranian dual nationals freed from Iran arrived in Britain on Thursday, ending an ordeal during which they became a bargaining chip in Iran's nuclear talks with the West.

British-Iranian aid worker Nazanin Zaghari-Ratcliffe and Anoosheh Ashoori arrived at the British military airbase of Brize Norton in Oxfordshire, shortly after 1 a.m. local time. They walked off the plane together and smiled and waved as they entered an airport building.

"It has been a really difficult 48 hours," British Foreign Secretary Liz Truss said shortly after Zaghari-Ratcliffe and Ashoori arrived at the base. "The expectation was that they would be released but we weren't sure right until the last minute so it's been very emotional but also a really happy moment for the families."

Zaghari-Ratcliffe's husband Richard said the long ordeal appeared to finally be over. "It's just a relief, the idea that we can go back to being a normal family, that we don't have to keep fighting, that this long journey is almost over," he told Reuters.

A statement from Ashoori's family thanked everyone who had worked towards his release. "1,672 days ago our family's foundations were rocked when our father and husband was unjustly detained and taken away from us.

Antonio Zappulla, CEO of Zaghari-Ratcliffe's employer, the Thomson Reuters Foundation, said her release was "a ray of light and hope" at a time when the world was in turmoil. The foundation is a charity that operates independently of Thomson Reuters and its news subsidiary Reuters.