"I am telling the Americans that we are absolutely determined and serious in defending our national security, our water borders, our shipping safety, and our security forces… and that all action will be met with a decisive response that will be efficient and quick," Major General Hossein Salami said.
“We have ordered our naval units at sea that if any warships or military units from the naval force of America’s terrorist army wants to jeopardize our commercial vessels or our combat vessels, they must target those (American) warships or naval units.”
"Americans have experienced our power in the past and must learn from it."
The latest confrontation between the archfoes came after the United States accused Iran of harassing its ships in the Persian Gulf last week.
Iran summoned the Swiss ambassador to Tehran, who represents US interests in the country, over recent Persian Gulf tensions.
Foreign Ministry spokesman Seyyed Abbas Mousavi said on Thursday the ambassador was given a message to pass on to the United States that Iran will strongly defend its maritime rights in the Persian Gulf and respond to any threats.
In the protest note, Iran “reminded the US administration of the necessity for all parties to commit to international maritime safety and free shipping regulations,” Mousavi said.
A US Navy statement has, however, alleged that 11 IRGC boats had closed in on six US naval vessels in the Persian Gulf “in dangerous and harassing approaches.” The IRGC strongly dismisses the statement, calling the account a “Hollywood tale”.
Salami said last week's maritime incident was the result of "unprofessional and dangerous behavior by the Americans in the Persian Gulf".
The International Crisis Group, noting the tensions, urged both countries to create a deconfliction hotline to avoid a possible military confrontation.
“In the absence of a major diplomatic breakthrough, an indirect military communications channel could go some way toward ensuring, at least, that a single incident will not spark a wider conflagration,” it said in a report Thursday.
Salami also indicated that US actions in the sensitive waterway had been affected by an outbreak of the novel coronavirus.
"In last week's incident, there was operational turmoil and disorder among US naval units at sea," said Salami.
This, he added, was an indication that the "command and control of their military units may have been weakened by... the coronavirus disease".
Iran and the United States are among the countries hardest hit by the coronavirus pandemic.
Iranian Foreign Minister Mohammad Javad Zarif suggested that the US should focus on saving American service members from the new coronavirus outbreak.
"The US military is hit by over 5,000 #covid19 infections...Also, US forces have no business 7,000 miles away from home, provoking our sailors off our OWN Persian Gulf shores," Zarif tweeted.
AFP, AP, Reuters and Press TV contributed to this story.