Jailed Iranian-American businessman Siamak Namazi has criticized the presence of Iran's foreign minister at Davos, saying his was convicted on charges of collaborating with the World Economic Forum.

In a letter to Foreign Minister Hossein Amir-Abdollahian on Saturday, the dual-national who has been imprisoned in Iran since 2015 asked how it is possible the Iranian diplomat attended the annual meeting in the Swiss resort while he was indicted for his cooperation with the forum. 

"The Revolutionary Court sentenced me to 10 years in prison -- in concurrence with the opinion of security officers -- stating that the purpose of the World Economic Forum from the young international elites' visit to Iran was networking for social movements and overthrowing [the government], and also recognized that this Swiss assembly is considered to be the same as the hostile US government," the letter read. 

He added, "If the ruling is correct, shouldn’t we ask what you were doing in Davos last week and why you attended the main conference of such a problematic institution?", and "If the court's interpretation is wrong, shouldn't we ask why I have been living in Evin [prison] for more than 2,400 days without any rights, such as a furlough.”

Siamak Namazi has been in prison since October 2015 on vague charges of collaboration with a foreign government. After Siamak’s arrest, his 84-year-old father, Bagher Namazi, a retired senior UNICEF official, traveled to Iran in 2016 to help him but he was also arrested and jailed in 2017 on vague accusations. Both are serving ten-year sentences.