Mark Wilmots has left his post as Iran's three-time Asian champions, seven months after taking over from Carlos Queiroz.
The former Belgian and Ivory Coast coach took charge in May to lead Iran to qualify for the sixth World Cup after Queiroz led them to their first two consecutive finals.
Iranian media reported on Wednesday that Wilmots had left by mutual consent.
While Velmots confirmed his contract with the Iranian federation had been terminated, he denied reaching an agreement by mutual consent.
"Contrary to the information circulated in the Iranian media, no agreement has been reached between me or one of my representatives with the Iranian Football Federation," he wrote in his Twitter account. "Lawyers take over everything and I will not comment."
Speculation in Iran that Wilmots did not lead the team against Iraq last month in the World Cup qualifiers has increased, but the Belgian coach was present at the match in Amman.
Iran lost the goal of Alaa Abbas in stoppage time, falling to third place, five points behind leaders Iraq, who played one more game.
The name of Branko Ivankovic, who led Iran to the 2006 World Cup and the current Peruvian coach, has been linked to taking over from Wilmots.
Iran play Hong Kong in Tehran in the next round of World Cup qualifiers on March 26.