Iranian Foreign Minister Mohammad Javad Zarif says unless it resorts to using “prohibited weapons,” the United States is not in any position to “obliterate” Iran as President Donald Trump has recently threatened.

Facing immense pressure at home for his inability to respond in kind to Iran’s downing of an intruding US spy drone last week, Trump said in a Twitter rant on Tuesday that Tehran will be met with “obliteration” if it ever attacks “anything American.”

Speaking to CNN on Wednesday, Zarif downplayed Trump’s remarks and said Washington was “incapable” of acting on such threats.

“He’s certainly wrong,” Zarif said. “But that statement indicates that the United States’ intentions are certainly illegal.”

“The United States is not in a position to obliterate Iran, they do not have the capability other than using prohibited weapons to do this,” he added.

“I think President Trump should remember that we don’t live in the 18th century,” the top diplomat noted. “There is a United Nations charter and threat of force is illegal.”

Last Thursday, the Islamic Revolutionary Guards Corps (IRGC) downed a US Navy RQ-4A drone inside the Iranian airspace over the Persian Gulf.

Trump said the following day that he had initially authorized airstrikes against three targets in Iran but called them off 10 minutes before launch.

Had it been a “manned” aircraft, his response would have been different, he said then.

This is not the first time that the Trump administration is threatening Iran with military action as a result of heightened tensions between the two sides over the past few weeks.

Trump stepped up his anti-Iran rhetoric after pulling out of the 2015 Iran nuclear deal in May last year and immediately launching a campaign of “maximum pressure” to force Tehran into negotiations on its ballistic missile program and growing regional influence.

In addition to several rounds of sanctions that target Iran’s economy, most notably it’s oil exports, Trump has also sent troops and military equipment to the Persian Gulf region to counter what it calls “threats” from Tehran.

It has also blamed a series of mysterious tanker attacks in the Sea of Oman to Iran without providing any evidence.

In its latest provocative move, the US imposed a series of bizarre sanctions that targeted Leader of the Islamic Revolution Ayatollah Seyyed Ali Khamenei and senior Iranian military commanders. The Trump administration is also set to introduce sanctions against Zarif in the coming days.

Zarif on Wednesday called the latest sanctions an “additional insult by the United States against the entire Iranian nation.”