"Threat for threat means that if the enemy fires a single bullet at us, it will receive 10 bullets and have to pay a heavy cost," Iranian armed forces general staff spokesman Brig. Gen. Abolfazl Shekarchi told Tasnim news agency in an interview.
He said that any act of aggression against Iran will draw such a "historic response that would make the assailants regret their move".
Brig. Gen. Shekarchi's comments came after Iran shot down a US Global Hawk surveillance drone earlier this week. Tehran said the unmanned US aircraft entered Iranian airspace in the early hours of Thursday. Washington, however, maintains it was shot down in international airspace.
Following the incident, US President Donald Trump said on Friday that he aborted a military strike to retaliate against Iran's move because doing so would have killed around 150 people.
In the interview with Tasnim, Shekarchi said that the Iranian Armed Forces were closely monitoring the US moves. "A military mistake from the enemy, particularly from the US and its regional allies, will be tantamount to firing at a powder keg... it will set the region ablaze and burn up the US, its interests and its allies."
He added that the Islamic republic "will never be the first side to start a war, but the enemy's slightest mistake will draw a revolutionary response from Iran in West and Central Asia from which the attackers would not survive".
Tension has been escalating between the two countries, with the US blaming Iran for last week's attacks on two oil tankers in the Gulf of Oman and on four tankers off the United Arab Emirates in May both near the Strait of Hormuz, through which between two and three dozen ships pass every day.
Tehran denies any role in these incidents.
Relations between the US and Iran plummeted to fresh lows after Trump decided to withdraw from the 2015 international nuclear deal and apply fresh sanctions targeting Iran's oil and banking sector.
( With inputs from IANS )