The force's programme 'will be unchanged from the time of his predecessor,' Supreme Leader Ayatollah Ali Khamenei said in a statement published by state media.
Iran's supreme leader appointed assassinated commander Qassem Soleimani's deputy, Brigadier General Esmail Ghaani, to replace him as head of the country's Quds Forces, Iranian media reported.
The force's programme "will be unchanged from the time of his predecessor," Supreme Leader Ayatollah Ali Khamenei said in a statement published by state media.
In latest escalation in the Iran-US tension, the United States killed Soleimani, head of the elite Quds Force and architect of Iran's spreading military influence in the Middle East, in a strike at Baghdad airport. Muhandis, an adviser to Soleimani, was also killed.
Rouhani also said that "Soleimani's martyrdom redoubled the determination to stand against America's bullying and defend Islamic values".
"There is no doubt that the great nation of Iran and the other free nations of the region will take revenge for this gruesome crime from criminal America," Rouhani said, referring to Iran's allies across the Middle East.
Soleimani's "martyrdom ... by the aggressor and criminal America has saddened the heart of the nation of Iran and all the nations of the region," he said in a statement posted on the Iranian government website.
His death had "redoubled the determination of the nation of Iran and other free nations to stand against America's bullying and defend Islamic values", said Rouhani.
Soleimani, who led the Quds Force, the foreign arm of the Revolutionary Guards and had a key role in fighting in Syria and Iraq, had acquired celebrity status at home and abroad. Over two decades he had been at the forefront of projecting the Islamic Republic's military influence across the Middle East.