America's top diplomat deserves a "punch to the mouth" over his vow to impose "the strongest sanctions in history" on Iran, according to a senior Iranian military commander.

On Monday, Secretary of State Mike Pompeo warned that the U.S. would take such action against Tehran unless the Islamic Republic changed course by meeting a list of 12 demands aimed at the heart of Iran's foreign policy agenda.

Ismail Kowsari, a senior officer with Iran's Revolutionary Guard who is deputy commander of the base responsible for security throughout Tehran, later responded.

"The people of Iran should stand united in the face of this and they will deliver a strong punch to the mouth of the American secretary of state and anyone who backs them," said Kowsari, according to the Iranian Labour News Agency.

The Revolutionary Guard was created after the Iran's 1979 Islamic Revolution to protect the ruling clerical establishment and is answerable to the country’s most powerful man, the supreme leader.

During his first major foreign policy address, Pompeo on Monday outlined a plan that included a reprieve from sanctions and restoration of full diplomatic and economic relations should Iran meet a list of 12 demands. The U.S. is demanding that Tehran essentially overhaul its regional and military policies, and the country's missile program is one of the administration's top concerns.

Pompeo's speech at the conservative Heritage Foundation came after President Donald Trump ended U.S. participation in the Iran nuclear deal, which also includes Britain, France, Germany, Russia and China.

According to Pompeo, the U.S. is pursuing a bigger Iran deal and asking for the support of U.S. allies beyond Europe, such as Australia, Japan, Jordan and Saudi Arabia.

International affairs analyst Bobby Ghosh, a foreign affairs columnist and former editor-in-chief of India's Hindustan Times, predicted that reaching a new pact would prove difficult.

"The trouble with this is that you have no partners going into the negotiation," he told NBC News' Kasie Hunt on MSNBC on Monday. "People with whom you were previously partners are now very, very upset ... and the other side it is not clear that they have any real incentive."

Other U.S. demands include that Iran pull out of Syria, where it has been fighting on the side of President Bashar al-Assad, end all military aspects of its nuclear program, stop uranium enrichment, and halt support for terrorist groups. Pompeo also demanded the release all U.S. citizens and those of U.S. partners and allies "detained on spurious charges or missing in Iran."

British Foreign Secretary Boris Johnson also said he believed the U.S. approach would be a tough sell.

"The idea of a jumbo Iran treaty [is] very difficult," he told reporters during a trip to Argentina.