WASHINGTON

The release of a Navy veteran from Iranian custody demonstrates that a pact with Tehran sought by the US for two years could be tenable, President Donald Trump said Thursday. 

Michael White left Iran earlier Thursday on board a Swiss jet.

He landed in Zurich, Switzerland and will "soon" board a plane for the US, Trump said on Twitter after earlier confirming his release.

"Thank you to Iran, it shows a deal is possible!" Trump said, likely referring to an agreement with the Islamic Republic he has sought since May 2018 when he unilaterally left the Joint Comprehensive Plan of Action (JCPOA) in May 2018 over the objections of all other signatories.

Trump maintains the nuclear accord was insufficient to rein in Tehran's nuclear program. He also wants a prospective agreement to cover all Iranian activities he considers to be "malign" in the region.

The JCPOA, brokered by the five permanent members of the UN Security Council, Germany, the EU and Iran, placed unprecedented curbs on Tehran's nuclear program in exchange for relief from biting economic sanctions Trump has gone on to reimpose, angering Iran.

Relations between the US and Iran have been at a fever pitch over the sanctions, a series of mysterious attacks in the region that Trump blames on Iran, as well as the president's decision to kill the former architect of Iran's regional military activities earlier this year.

White, whose family says suffers from underlying health conditions, was among a wide batch of prisoners who were granted furlough from prison in Iran because of concerns for their health as the coronavirus rapidly spreads in that country. He reportedly tested positive for COVID-19.

White's release follows the deportation of an Iranian scientist earlier this week. Sirios Asghari was acquitted of fraud and trade secret theft in November, but had reportedly been held in immigration custody in the time since and had contracted the coronavirus.