Sudan's foreign ministry has denied that Iran had any connection to a military factory which Khartoum says was attacked by Israeli aircraft last week.
The denial coincided with the arrival of two Iranian navy ships, the helicopter carrier Kharg and destroyer Admiral Naqdi, at Sudan's Red Sea port.
"The ministry of foreign affairs confirms what is known by all: that Iran has no need to manufacture weapons in Sudan, for Iran or for its allies," the ministry said in the statement on Monday.
"We want to deny any relation between Sudan's military manufacturing and any foreign partner."
According to Iran's official IRNA news agency, the ships were sent to the Djibouti area in September, media reports said, adding that they were carrying "the message of peace and friendship to neighbouring countries and were ensuring security for shipping lanes against maritime terrorism and piracy."
Sudan's links to Iran have come under scrutiny after the country accused Israel of sending four radar-evading aircraft to strike the Yarmouk military factory in the heart of Khartoum at midnight last Tuesday.
Israeli officials have expressed concern about arms smuggling through Sudan, and have long accused Khartoum of serving as a base of support for militants from the Islamist Hamas movement that rules the Gaza Strip.
Israel refused all comment on Khartoum's allegations about the factory blast.
An 'outlaw state'
But a top Israeli defence official, Amos Gilad, said last week that Sudan "serves as a route for the transfer, via Egyptian territory, of Iranian weapons to Hamas and Islamic Jihad terrorists".
Sudan's foreign ministry called Israel an "outlaw state... trying its best to pass fabricated information through different sources that have a link with Israel, in an effort to provide reasons for its aggression.
"This includes talk about claimed relations between the al-Yarmouk compound and Iran and Syria, and the Hamas Islamic struggle movement in Palestine, and Hezbollah in Lebanon."
The foreign minister, Ali Ahmed Karti, also said he had filed a complaint at the United Nations Security Council over the alleged airstrike.
Jonah Leff, of Small Arms Survey, a Swiss-based independent research project, said the project has documented the presence of a drone, landmines and other Iranian weapons in Sudan, but he thinks they were acquired directly from Iran rather than being locally manufactured.
"There's a lot of speculation that Iran has provided technical assistance to the Sudanese for their weapons manufacturing but I haven't been able to confirm that they're producing any Iranian weapons," he told the AFP news agency on Thursday.
Evidence from weapons packaging suggests that Chinese-origin arms and ammunition are exported to Yarmouk, Small Arms Survey says.
Ahmed Bilal Osman, Sudan's information minister, said that "traditional weapons" are made at the factory.
On a visit to Tehran last August, Sudanese President Omar al-Bashir described the relationship between Sudan and Iran as "deeply rooted."
In April last year, Sudan said it had irrefutable evidence that Israeli attack helicopters carried out a strike on a car in Red Sea state.
That incident mirrored a similar attack by foreign aircraft on a truck convoy reportedly laden with weapons in eastern Sudan in January 2009.