Two Iranian warships docked in Sudan on Monday, Iran's official IRNA news agency reported, less than a week after Khartoum accused Israel of attacking an arms factory in the Sudanese capital.
Two people were killed after fire broke out late on Tuesday at the Yarmouk arms factory in the south of Khartoum. Sudanese Information Minister Ahmed Belal Osman said four military planes attacked the Yarmouk plant and Israel was behind it.
Asked by Israel's Channel Two News about Sudan's accusations, Israeli Defense Minister Ehud Barak said: "There is nothing I can say about this subject."
IRNA said the helicopter carrier Khark and the destroyer Shahid Naqdi were carrying: "the message of peace and friendship to neighbouring countries and were ensuring security for shipping lanes against marine terrorism and piracy".
Iran's semi-official Fars news agency said that the vessels docked in Port Sudan on the Red Sea and the fleet's commanders were scheduled to meet Sudanese navy commanders.
Sudan, with close ties to Iran and Sunni jihadis, has long been seen by Israel as a conduit for weapons smuggled to the Hamas-ruled Gaza Strip, via the Egyptian Sinai desert.
In May, Sudan's government said one person had been killed after a car exploded in the eastern city of Port Sudan. It said that explosion resembled a blast last year it had blamed on an Israeli missile strike.
Israel declined to comment on the May incident or the 2011 blast, which killed two people. It also neither admitted nor denied involvement in a similar incident in eastern Sudan in 2009.
Iran said in June it had plans to build more warships and increase its presence in international waters, particularly to protect its cargo ships around the world.
Pirates in the Gulf of Aden in January hijacked an Iranian ship carrying 30,000 tonnes of petrochemical products to a North African country.