Press TV - Freed Iranian stem cell scientist Dr. Masoud Soleimani has arrived in Tehran after over one year of imprisonment in the United States.

Soleimani arrived at Tehran Mehrabad airport on Saturday evening� after he was released by the US in a prisoner swap. He was welcomed by his family members and Iranian officials upon his arrival.

Iranian Foreign Minister Mohammad Javad Zarif accompanied the released scientist�from Zurich where the swap took place.

The Iranian foreign minister said in a tweet earlier in the day that the top scholar, along with Xiyue Wang � a Chinese-born US citizen who had been sentenced to 10 years in prison for espionage in Iran in 2017 � had been delivered to the Swiss officials and would �be joining their families shortly.�

Speaking to reporters at the airport, Zarif said he is "very happy that on National Students� Day, one of the greatest professors and scientists of our country is returned home."

He added that Dr. Soleimani had been taken hostage by the American forces for 14 months "without any reason."

The US "arrested a university professor with 500 scientific articles without any reason" after it invited him and gave him a visa "to do research at the highest US scientific institute."

The top Iranian diplomat emphasized that Dr. Soleimani had been repeatedly offered by the United States to stay in the US instead of returning home but the �patriotic professor" turned down their request.

Zarif also thanked Iran's Supreme National Security Council, the Judiciary and security bodies for agreeing to the Iranian scientist's swap with an American who was held in Iran on espionage charges and was pardoned based on �Islamic compassion� and returned to the US.

"Over the past 40 years, the US has been trying to hinder Iran's scientific progress. The US� maximum pressure has been pursuing such a goal," he said.

Zarif added that the science, progress and technology that the Iranian nation has managed to acquire trough its self-reliance are the "biggest thorn in the side of those who do not want this nation's prosperity."

For his part, Soleimani said Iran�s achievements in science and technology have made the US angry and that is the main reason behind Washington's animosity towards Tehran.

He called on Iranians to build up the country�s scientific front to further make the enemy disappointed.

He also thanked Iranian officials for securing his release.

In a tweet, President Donald Trump thanked Tehran for a "very fair" negotiation that led to the release Saturday of an America held in Iran and an Iranian scientist jailed in the US.

"Thank you to Iran on a very fair negotiation. See, we can make a deal together!"

Back in October last year, Soleimani, 49, left Iran on sabbatical last year but was arrested upon arrival in Chicago and transferred to prison in Atlanta, Georgia for unspecified reasons.

When he left Tehran last fall, Soleimani, a professor and biomedical researcher at Tarbiat Modares University (TMU) in Tehran, planned to complete his research on treating stroke patients as a visiting scholar at the prestigious Mayo Clinic in Minnesota.

Prosecutors in Atlanta had accused him and two of his former students of conspiring and attempting to export vials of human growth hormone from the US to Iran without authorization, in violation of US sanctions.

The human growth hormone is not banned in the US or Iran and was being used �exclusively for medical research,� which is still considered largely exempt from US sanctions, according to his Atlanta attorney Leonard Franco.

The two students were charged in a court and released after posting bail because they held US citizenship.