BBC: Iran has released a Lebanese businessman imprisoned on charges of spying for the United States, Lebanon's state news agency reports.

Nizar Zakka, who has US permanent residency, was on a plane to Beirut with General Security chief Gen Ibrahim Abbas, the National News Agency said.

The information technology expert was arrested while visiting Tehran in 2015.

Lebanese media reported that Zakka had been pardoned at the request of Lebanon's President, Michel Aoun.

But Iranian state TV cited official sources as saying that his release was secured only following the intervention of Hassan Nasrallah, the leader of the Iran-backed Lebanese militant group Hezbollah.

Zakka is one of a number of dual citizens and foreign nationals detained in Iran, mostly on spying charges, in recent years. The Americans being held include:

* Baquer Namazi and Siamak Namazi - the former UN official and his son, a businessman, were both sentenced to 10 years in prison in 2016

* Karen Vafadari and Afarin Neyssari - a Zoroastrian couple who own an art gallery, were sentenced to 16 and 27 years in prison in 2018

* Xiyue Wang - a doctoral student conducting historical research, was sentenced to 10 years in prison in 2017

* Morad Tahbaz - an environmental activist, was arrested in 2018

Zakka, who is in his 50s, is an advocate for internet freedom and is secretary-general of the Beirut-based Arab ICT Organisation (IJMA3), an alliance of information communications technology associations from 13 countries across the Arab world that has worked for the US government.

In September 2015, he travelled from his home in Washington DC to Tehran to attend the International Conference and Exhibition on Women in Sustainable Development.

He had been invited to speak by Iran's then Vice-President for Women and Family Affairs, Shahindokht Molaverdi >>>