US State Department spokesman John Kirby
© AFP 2016/ MANDEL NGAN
The US government did not transfer $400 million to Iran in exchange for the release of four US citizens, US State Department spokesman John Kirby said Wednesday.

The Wall Street Journal reported earlier in the day that wooden pallets stacked with euros, Swiss francs and other currencies were flown into Iran on an unmarked cargo plane, as the US law forbids transacting US dollars with Iran. At the same time, the United States was negotiating a prisoner exchange with Iran, raising doubts among Republicans that money had changed hands to guarantee the release as a ransom payment.

"The funds that were transferred to Iran were related solely to the settlement of a long-standing claim at the U.S.-Iran Claims Tribunal at The Hague," Kirby said, as quoted by the Fox News.

In January, the United States transferred the first installment in a $1.7 billion settlement the Obama administration reached with Iran to resolve a failed 1979 arms deal dating from before the Iranian Revolution, which was negotiated in the framework of the Iran-US Tribunal. According to the Wall Street Journal, the Obama administration actually secretly organized an airlift of $400 million worth of cash to Iran that coincided with the January release of four Americans detained in Tehran.

"The negotiations over the [arms deal] settlement...were completely separate from the discussions about returning our American citizens home. Not only were the two negotiations separate, they were conducted by different teams on each side," Kirby added.

The four US nationals who had been arrested and imprisoned in Iran were released on January 16. In return, the Obama administration agreed to release seven Iranians either jailed or facing charges in the United States.

The Iran-United States Claims Tribunal was established in January 1981 to resolve the hostage crisis, but has continued its work since. To date, the Tribunal has finalized over 3,900 cases.