On Sunday, in its most explicit warning to Donald Trump not to revise the terms of the Nuclear Deal - something the US president is expected to do over the coming days - Iran warned the United States that U.S. regional military bases "would be at risk" if further sanctions were passed. "The Americans should know that the Trump government’s stupid behavior with the nuclear deal will be used by the Islamic Republic as an opportunity to move ahead with its missile, regional and conventional defense program," Iran Revolutionary Guards’ commander Mohammad Ali Jafari said, quoted by Reuters. He then threatened US presence in the region, warning that “if America’s new law for sanctions is passed, this country will have to move their regional bases outside the 2,000 km range of Iran’s missiles."

Then, one day later, Iran vowed on Monday to give a "firm and crushing" response should Washington decide to also include the elite wing of its army, the Islamic Revolutionary Guard Corps (IRGC), on its list of terrorist organizations, according to the country’s foreign ministry.

"We are hopeful that the United States does not make this strategic mistake,” Iranian Foreign Ministry spokesman Bahram Qasemi stated during a news conference according to Reuters. “If they do, Iran’s reaction would be firm, decisive and crushing and the United States should bear all its consequences."



Members of the Iranian Revolutionary Guard Corps

Late last week, the White House disclosed that Washington is preparing tougher sanctions on Tehran, including the possible designation of the Islamic Revolutionary Guard Corps (IRGC) as a terrorist group. The Trump administration aims to put more pressure on the IRGC, especially over recent missile tests and what Washington has called its “malign activities” across the Middle East. The U.S. government imposed sanctions in July on 18 entities and people for supporting the IRGC in developing drones and military equipment. In August, Congress overwhelmingly approved the “Countering America’s Adversaries Through Sanctions Act” which imposed new sanctions on Iran for its ballistic missile program, as well as sanctions on Russia and North Korea.

The Iranian counter-threats came from Qasemi one week before President Donald Trump is expected to announce his final decision on how he wants to contain the Islamic Republic. On October 15, Trump is expected to “decertify” the landmark 2015 international deal to curb Iran’s nuclear program, a step that by itself stops short of pulling out of the agreement but gives Congress 60 days to decide whether to reimpose sanctions.

New U.S. sanctions on the IRGC could affect conflicts in Iraq and Syria, where Tehran and Washington both support warring parties that oppose the Islamic State militant group (IS).

France said on Monday it was worried that classifying the IRGC as a terrorist group could exacerbate tensions in the region.

Germany said it was worried Trump would decide Iran is not respecting the nuclear deal, negotiated under his predecessor Barack Obama, and fears such a step will worsen insecurity in the Middle East.

Then there was Russia: Moscow warned on Monday there would be "negative consequences" if US President Donald Trump fails to uphold the landmark Iran nuclear deal negotiated by his predecessor.

"Obviously if one country leaves the deal, especially such a key country as the US, then that will have negative consequences," Russian President Vladimir Putin's spokesman said. "We can only try to predict the nature of these consequences, which we are doing now," Dmitry Peskov told journalists.

A U.S. pullout from the Iran deal will unravel an accord seen by supporters as vital to preventing a Middle East arms race and tamping down regional tensions, since it limits Iran’s ability to enrich uranium for nuclear fuel in exchange for the lifting of sanctions that damaged its oil-based economy. As a reminder, prior to the deal Iran and Israel were constantly at each other's throats, resulting in a constant fear of imminent war between the two nations.

Meanwhile, the U.N. nuclear watchdog’s inspectors have repeatedly declared Iran in compliance with the terms of the nuclear deal.

That was not enough for Trump, who called Iran “a corrupt dictatorship” during his first speech to the U.N. General Assembly and said the nuclear deal was “the worst and most one-sided transactions the United States has ever entered into”. The other five world powers in the deal were Britain, France, Germany, Russia and China. The prospect of the United States reneging on the agreement has worried other partners that helped negotiate it.

British Prime Minister Theresa May, who supports the nuclear pact, and Israeli Prime Minister Benjamin Netanyahu, who opposes it, agreed in a phone call on Monday that they need to be “clear-eyed” about the threat Iran poses to the Middle East. “They agreed that ... the international community should continue working together to push back against Iran’s destabilizing regional activity,” May’s spokesman said.

In an interview aired on Saturday night, Trump accused Iran of “funding North Korea” and “doing things with North Korea that are totally inappropriate”. Qasemi responded that U.S. accusations were “baseless”. He added, “Israel and some specific countries are raising these accusations to create Iranophobia.”

Finally, should Trump go ahead and designate the IRGC terrorists, University of Tehran analyst Seyed Mohammad Marandi said that Tehran will give a similar designation to the US military. Asked by RT, if he expects Trump to decertify the nuclear deal on October, 15, and what impact this could have on stability in the world, Marandi responded: