Iran is so adamant about removing Islamic Revolution Guard Corps (IRGC) from the US "terrorist blacklist", IRNA said citing a source close to Iran's nuclear-negotiating team.

This statement comes in response to the Wall Street Journal's report which claims that Tehran has dropped its demand that the IRGC be removed from Washington's "terrorist blacklist" in exchange for sanctions relief in order to complete the stalled efforts to restart the nuclear deal.

Iran has “good intentions” and is “serious” about reaching an agreement to revive the nuclear deal, IRNA said.

Iranian top nuclear negotiator Ali Bagheri Kani said Wednesday that the goal of the negotiations is to determine the conditions for the US' return to the nuclear agreement.

The US cannot set the conditions for Iran, which is a member of the agreement, he added.

Kani stressed that the round of negotiations in Vienna is a test of the seriousness and realism of Washington to reach an agreement.

The ball is in Washington's court to save Iran's 2015 nuclear deal with world powers, Kani tweeted ahead of his trip to Vienna, where Iran and the US will resume indirect talks to try to secure the pact.

"Heading to Vienna to advance the negotiations. The onus is on those who breached the deal & have failed to distance from ominous legacy," Bagheri Kani tweeted.

The United States and Iran resumed indirect talks regarding the revival of the 2015 nuclear deal in Vienna on Thursday. 

US officials are concerned that the nuclear deal is on the verge of becoming obsolete, as Iran has taken efforts to advance its nuclear program following the adoption of a politically-motivated anti-Iran resolution by the UN.

Read more: The ball is in Washington's court, will not offer more in Vienna: Iran