The sources - a European diplomat, a European intelligence official and a U.S. official - said it was not clear why Iran did not supply launchers with the Fath-360 missiles, raising questions about when and if the weapons will be operational.
The U.S. official, who like the other sources spoke on condition of anonymity, said Iran had not delivered the launchers at the time of the U.S. announcement about Iran's delivery of the weapons. The European intelligence official said without elaborating that they did not expect Iran to provide launchers.
Two experts told Reuters there could be several reasons why the launchers were not sent. One is that Russia may plan to modify trucks to carry the missiles, as Iran has done. Another is that by withholding the launchers, Iran is allowing space for new talks with Western powers on easing tensions.
The Russian defense ministry declined to comment.
The U.S. National Security Council did not immediately respond to a request for comment and the Pentagon declined to comment.
Iran’s mission to the United Nations did not immediately respond to a request for comment.
Tehran denies providing Moscow with the missiles or with thousands of drones that Kyiv and Western officials have said Russia uses against military targets and to destroy civilian infrastructure, including Ukraine’s electrical grid.