In a tweet on Wednesday, Javad Zarif said that Iran’s missile program grew out of the 1980-1988 war against Saddam Hussein’s Iraq.

“For 8 YEARS, Saddam showered our cities with missiles & bombs provided by East & West,” Zarif wrote. “Meanwhile, NO ONE sold Iran any means of defense. We had no choice but building our own. Now they complain.”

“Instead of skirting the issue, US must end arms sales to Saddam’s reincarnations,” Zarif also said.

In an interview with NBC News that aired earlier this week, Zarif said that if the U.S. wants to discuss Iran’s missile development, it needs “first to stop selling all these weapons, including missiles, to our region.”

Iran has long rejected negotiations over its ballistic missile program, which remains under the control of the Iranian paramilitary Revolutionary Guard, which answers only to the country’s supreme leader, Ayatollah Ali Khamenei.

The foreign minister’s comments seemed to suggest an opening for talks amid high tensions between Tehran and Washington. But the Iranian mission to the United Nations promptly called Zarif’s suggestion purely “hypothetical” and said the Iranian missiles were “absolutely and under no condition negotiable with anyone or any country, period.”

Abbas Mousavi, a spokesman for the country’s Foreign Ministry, tweeted late on Tuesday that Zarif’s remarks were meant to challenge Washington and “threw the ball into the U.S. court while challenging America’s arm sales” to its Middle Eastern allies.