The docking of two Iranian warships in Sudan raises Israeli concerns about arms smuggling to Hamas.
Two Iranian warships docked in Port Sudan on Saturday, a witness said, marking the second port call by the Iranian navy in Sudan in five weeks.
The Iranian navy said the 1,400 ton frigate Jamaran and the 4,700 ton support ship Bushehr "docked in Port Sudan, after successfully carrying out their assignments in the Red Sea and were greeted by high-ranking Sudanese naval commanders."
It did not say how long the warships would stay in port.
Khartoum said it was a "normal" port call but Israeli officials have expressed concern about arms smuggling through Sudan.
They have long accused the African country of serving as a base of support for militants from the Palestinian Islamist movement Hamas which rules the Gaza Strip.