The planned corridor, dubbed the "Trump Route for International Peace and Prosperity", is a key part of a peace deal signed at the White House on Friday between Azerbaijan and its longtime foe Armenia.

However, the proposed route, in which the United States will have development rights, passes near the Iranian border and Khamenei's international affairs adviser Ali Akbar Velayati said Iran would not accept it.

"With the implementation of this plot, the security of the South Caucasus will be endangered," Velayati told the Tasnim news agency,

He said the planned corridor was "an impossible notion and will not happen", while the area would become "a graveyard for Trump's mercenaries".

Iran has long opposed the planned transit route, also known as the Zangezur corridor -- fearing it would cut the country off from Armenia and the rest of the Caucasus, and bring a foreign presence to its border.

"We have the right to defend our interests in a completely powerful manner," Velayati said, adding that Iran had held multiple military exercises in the area to show its "readiness".

Iran's foreign ministry welcomed "the finalisation of the text of the peace agreement" between Armenia and Azerbaijan but expressed "concern over the negative consequences of any foreign intervention in any way and form, especially in the vicinity of common borders".

It added that such a move would "disrupt the security and lasting stability of the region."

Christian-majority Armenia and Muslim-majority Azerbaijan have feuded for decades over their border and the status of ethnic enclaves within each other's territories.

They went to war twice over the disputed Karabakh region, which Azerbaijan recaptured from Armenian forces in a lightning 2023 offensive, sparking the exodus of more than 100,000 ethnic Armenians.

Asked what Armenia stood to gain from Friday's deal, a White House official said it was "an enormous strategic commercial partner, probably the most enormous and strategic in the history of the world: the United States of America".

"The losers here are China, Russia and Iran," he said, speaking on condition of anonymity.