A former three-time Iranian Presidential candidate says the US and Israel made a huge mistake in killing Supreme Leader Ali Khamenei and that the Americans are increasingly desperate for the conflict to end.

Hooshang Amirahmadi, who stood for the Iranian Presidency in 2005, 2013 and 2017, said the Ayatollah's killing had complicated any future peace negotiations by splintering the leadership of the Islamic Revolutionary Guard Corps into uncontrollable localized divisions.

Seventy-eight-year-old Amirahmadi also believes US President Donald Trump is caught between fearing the economic fallout caused by the conflict and the advice of the 'warmongers' in his camp.

Amirahmadi told CGTN: "The biggest mistake of this war from Mr. Trump and Netanyahu's side was to kill Khamenei. Mr. Khamenei was a controlling force. It was a brake on the revolutionaries and on the military and that brake has been taken off."

He argued that Khamenei's killing had "liberated" revolutionary groups who are now "doing what they think should be done in the field." He explained: "We have 31 provinces in Iran, and there are 31 (groups of) Revolutionary Guards…each of them is the king of the castle they control." 

The elimination of Iran's top generals and leaders in Tehran has magnified the error, he believes. "De facto, the people at the lower level, middle level are in charge, and I call them the colonels, as opposed to generals, and these people are obviously more patriotic than those at the very top that were eliminated." 

As the conflict enters its fifth week, Amirahmadi said both sides are in a "deadlock war" which will not end any time soon, despite Trump's initial predictions that the US would win a lightning campaign. 

He opined: "I know that the US side is trying to find every opportunity to end it because they already have recognized that they may have made a big mistake."

Amirahmadi is the founder and president of the American Iranian Council, a US-based bi-partisan think tank focused upon promoting better relations between the US and Iran.

He fears that the campaign will not end any time soon, saying: "On the one hand, President Trump promises this to be a short-term war, and then at the same time, he's sending thousands of soldiers and other military assets to the region and thinking of taking over a few Iranian islands, and if that is the plan, then you are talking real long term."

Describing Trump's behaviour as "contradictory", Amirahmadi - who now lives in the US - said Trump is caught between two stools, as he tries "to balance between the war and the market." He said: "The market doesn't like this war, but the warmongers obviously are pushing for it. So there is a real struggle in this country between the market and the warmonger."

Amirahmadi, who has published extensively on the topic of Middle-Eastern relations, described Tehran's strategy as one of deterrence which counterintuitively fitted its tactic of bombing Gulf neighbors. 

He said: "Tehran knows that by sending missiles to Saudis, to the Emirates, or to Israel even, it cannot end the war. It cannot damage these countries in a significant way. But at the same time, this has been actually from their perspective a good deterrence. Its hits to the Arab countries (and) closing the strait of Hormuz has put tremendous pressure on the United States and President Trump to find a solution." 

He added: "The Arab world are pressuring the United States because….they really don't know what to do. They were expecting to be defended by the US and obviously the US is not in a position to defend them to the extent that they wanted. At the same time, the Arab countries don't want to get into this war.

"Iran's strategy by attacking nations in the region is a deterrence strategy. It is trying to make the US end the war."