The U.S. state Department on Saturday, September 29, announced the evacuation of the U.S. Consulate in the Iraqi city of Basra.
"The ridiculous justification [provided by Americans] for the closure of the U.S. Consulate General in Basra, which came after weeks of propaganda and false allegations against Iran and the Iraqi forces, is a suspicious move aimed at evading responsibility and pinning the blame on others", Qassemi stated.
The decision adds to mounting tension between the United States and Iran, which is the target of increasing US economic sanctions.
Since July 9, Iraq's Shia-majority central and southern provinces - especially Basra - have been rocked by protests to demand better public services, more job opportunities and an end to government corruption.
In mid-September, the White House warned that it would hold Iran responsible for any attack by groups backed by Tehran against American nationals or U.S. interests in Iraq.
"The ministry regrets the American decision to pull its staff out of Basra", a statement said.
"I have made clear that Iran should understand that the United States will respond promptly and appropriately to any such attacks". In Baghdad in early September, assailants fired three mortar rounds into the Green Zone, a heavily fortified area which is home to the Iraqi parliament, government offices and the USA embassy.The rare attack did not cause casualties or damage.
He said that Washington was working with Iraqi forces and US allies to address the threats.
It also comes following heated exchanges at the UN General Assembly this week, where US President Donald Trump accused Iran of sowing "chaos, death and destruction" across the Middle East.
Earlier this month, protesters in Basra set alight government and political buildings, including the Iranian consulate and the headquarters of an Iran-backed paramilitary force, after a number of people were killed in clashes with police.
At the United Nations this week, the two sides taunted each other, with Mr Trump's national security adviser, John Bolton, warning Iran there would be "Hell to pay" if it crosses the US.
Despite Iran's defiance of Trump's demands, his move in May to withdraw the United States from Iran's 2015 nuclear deal with world powers and reimpose US economic sanctions has contributed to a major loss in the value of the country's currency, the rial, and an economic slump this year.
The American diplomat claimed Iran was trying to use the potential risk to USA staff there as a form of leverage on the administration of Donald Trump and his anti-Iran policies.