A US Navy veteran detained in Iran for nearly two years flew out of the country on Thursday after US authorities released an Iranian scientist.
"I am blessed to announce that the nightmare is over, and my son is safely on his way home," Michael White's mother, Joanne White, said in a statement quoted by AFP.
White had tested positive for COVID-19 and received treatment in Iran, said Bill Richardson, a former US ambassador who said he met senior Iranian officials to win his release.
Both Iran and President Donald Trump's administration insisted that there was no swap involving Cyrus Asgari, an Iranian scientist acquitted by a US court who returned to Tehran on Wednesday.
Trump hailed White's release and said he was returning home on an airplane sent by Switzerland, which represents US interests in Iran in the absence of diplomatic relations.
"I will never stop working to secure the release of all Americans held hostage overseas! Thank you Switzerland for your great assistance," Trump wrote on Twitter.
In a later tweet, Trump wrote, “We have now brought more than 40 American hostages and detainees back home since I took office. Thank you to Iran, it shows a deal is possible!”
White, who had served 13 years in the US Navy, was arrested in July 2018 in the northeastern city of Mashhad after visiting a woman whom he had reportedly met online.
He was sentenced the following year to at least 10 years in prison on charges that he insulted Iran's Supreme Leader Ayatollah Ali Khamenei and posted anti-regime remarks on social media under a pseudonym.
In March, as Iran was being hit hard by the coronavirus pandemic, White was handed over to Swiss custody and flown to Tehran but told not to leave the country.
Richardson said White, who is in his 40s and had pre-existing medical conditions, was admitted to a hospital for treatment but otherwise stayed at a hotel in Tehran.
The release of White comes despite ongoing tensions between the US and Iran. The US Navy recently issued a warning to mariners in the Gulf to stay 100 meters away from US warships or risk being “interpreted as a threat and subject to lawful defensive measures”.
While no mention was made of Iran in the notice, it follows Trump’s threat last month to fire on any Iranian ships that harass Navy vessels.
Trump’s warning followed a tense encounter between US and Iranian ships in the Persian Gulf.
The tensions have been escalating since Trump withdrew from the 2015 Iran nuclear deal and reimposed sanctions on the Iranian economy.