"(All) necessary measures have been taken in this regard," Hossein Amirabdollahian said in a Sunday interview.
"In addition to following all (available) legal channels, we have declared and registered then US administration's responsibility in the assassination through an official memo, and will follow up on our lawsuit through its own natural path," he added.
"Unfortunately, both the Americans and (other) Western (countries are trying to) stonewall and obstruct the process of legal pursuit of the case," the Iranian minister stated, Press TV reported.
"The Islamic Republic's hands are not tied, though," he asserted, noting that, in parallel to its legal efforts, the country is taking other punitive measures against those responsible for the assassination of General Soleimani.
Among these measures, Amirabdollahian said, Iran has placed the names of 60 relevant American officials, who have had a hand in the assassination, on its terrorist blacklist.
The American side has, through indirect channels, explained to the Islamic Republic that the blacklisting has prompted Washington to invest "exorbitant expenses" in ensuring those officials' safety both inside the United States and during their overseas' trips, Amirabdollahian said.
Iran has, however, stood firm by its decision, calling the blacklisting a "precise and correct" measure, said the foreign minister.
"We will follow up on this (measure) through political, legal and international channels, so these individuals will be brought to justice," he said, reiterating that the Iranian Foreign Ministry would not spare any effort as it pursues the case of the assassination.
The United States assassinated General Soleimani, the former commander of the Islamic Revolution Guards Corps (IRGC)'s Quds Force, along with Abu Mahdi Al Muhandis, deputy commander of Iraq’s anti-terror Popular Mobilization Units, and their companions, in a drone strike near the Baghdad International Airport on January 3, 2020.