Ambassador Hassan Danayeefar told the semiofficial Fars News Agency his government hasn't reached a military sales agreement with Baghdad.
"If the Iraqi government raises any such demand to control and fight terrorism, which is every country's duty responsibility today, we will be ready to consider it," he said.
Iraq is struggling to control the resurgence of al-Qaida in restive Anbar province, a region with a large Sunni population. U.S. forces twice took on militants in the province before ending combat operations in 2011.
U.S. State Department spokeswoman Jen Psaki said during a press conference Monday the U.S. government would have concerns if such a deal materialized.
She said Iraq is a sovereign country that has the authority to pursue its own national interests. Existing sanctions pressure on Iran, however, meant Iraq "should use caution" in any outreach effort with Iran.
The U.S. military, she added, has made "a number" of weapons shipments to Iraq as part of a foreign military sales program.