Iran said Friday that it had "indisputable" evidence that a US drone it shot down this week had violated its airspace.
Deputy foreign minister Abbas Araghchi told Swiss ambassador, Markus Leitner, whose country represents US interests in Iran, of the evidence on Thursday night, the foreign ministry said in a statement.
"Even some parts of the drone's wreckage have been retrieved from Iran"s territorial waters," Araghchi told the Swiss envoy."
Araghchi urged US forces to "respect Iran's aerial and maritime borders and fully abide by international regulations," the ministry said.
He "reiterated that Iran does not seek a war and conflict in the Persian Gulf, warning the American forces against any unconsidered measure in the region," it added.
"The Islamic Republic of Iran would not hesitate for a moment to decisively defend its territory against any aggression," the statement quoted Araghchi as saying.
Foreign Minister Mohammad Javad Zarif said Thursday that Iran would go to the United Nations to prove that the drone had entered its airspace before being shot down.
Thursday's downing -- which Washington insists was above international waters -- has seen tensions between the two countries spike further after a series of attacks on tankers the US has blamed on Iran.