The new chief of Iran’s Quds Force, Esmail Qaani, has threatened to take revenge on the US after the assassination of his predecessor, Gen Qassem Suleimani.
Brig Gen Qaani's remarks come amid the most significant confrontation between Tehran and Washington in decades, escalating tension in the region, especially in Iraq, where Suleimani was killed.
"God the almighty has promised to get his revenge … certainly actions will be taken," Brig Gen Qaani told Iranian state television on Monday.
The Quds Forces is a unit of Iran's Islamic Revolutionary Guard Corps and oversees an array of militant proxies, as well as organising Iran’s operations in the region.
Washington has sanctioned Brig Gen Qaani since 2012 for his work funding Quds Force operations across the world, including its work with proxies in Iraq, Lebanon and Yemen.
"We promise to continue down martyr Suleimani's path as firmly as before with help of God, and in return for his martyrdom we aim to get rid of America from the region," Brig Gen Qaani said.
Suleimani’s daughter, Zainab, joined Brig Gen Qaani in threatening US military forces stationed in the region while speaking to hundreds of thousands of supporters in Tehran.
“The families of US soldiers in the Middle East will spend their days waiting for the death of their children," she said.
The killing of Suleimani came amid months of back-and-forth attacks that have put the wider region on edge.
US President Donald Trump said on Twitter that Washington would strike back at 52 targets “very fast and very hard" if Tehran took any steps against US troops in the region.
"If Iran attacks an American base, or any American, we will be sending some of that brand new beautiful equipment their way … and without hesitation!" Mr Trump said.
Iran's supreme leader, Ayatollah Ali Khamenei, along with top officials in Tehran, led prayers in a state funeral for Suleimani on Monday.
Tehran also said it has abandoned the remaining limits of its 2015 nuclear deal with world powers in response to the killing.
Iraq's parliament responded by voting on Sunday to oust US troops from the country.
Mr Trump threatened to impose sanctions on Iraq if US forces were forced to leave, saying Iraq's government would have to pay Washington for the cost of a "very extraordinarily expensive" airbase in the country.