Sudan's army spokesman Sawarmi Khaled Saad said the warships, one of them a navy supply ship, had arrived in Port Sudan.
They would refuel and then continue elsewhere, he said, adding that during their port call civilians could tour the Iranian ships.
Naval vessels from Iran have periodically stopped in Port Sudan for what Khartoum described as normal port calls.
Port Sudan lies about 250 kilometres across the Red Sea from Saudi Arabia, which has long been wary of Iran's regional ambitions.
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Khartoum also has close ties with Qatar, which is perceived as supporting the Egypt-based Muslim Brotherhood which Saudi Arabia and other Gulf monarchies have long been hostile to.
Relations between Sudan and Saudi Arabia are "zero", a senior Sudanese opposition politician told AFP last month.
Ibrahim Ghandour, the chief assistant to President Omar al-Bashir, said in a March interview that there is "nothing peculiar" in Sudan's relations with Iran, which he said has not affected ties with other neighbours including Saudi Arabia which remains a leading investor.