Russia has been supplying Iran with intelligence on the locations of U.S. military assets in the Middle East, marking the first indication that another major U.S. adversary is indirectly participating in the ongoing conflict, according to three officials familiar with the matter.

The assistance reportedly includes targeting information on U.S. warships and aircraft, according to a report by The Washington Post, which cited officials familiar with the intelligence. 

One source told The Washington Post that Moscow’s support appears to be “a pretty comprehensive effort,” though the precise accuracy and scope of the intelligence being provided remain unclear.

The revelation underscores the growing complexity of the conflict in the region, as multiple global powers become involved directly or indirectly in the hostilities between Iran, Israel, and the United States.

U.S. officials have not publicly confirmed the extent of Russia’s involvement but described the intelligence as “significant” to ongoing military operations.