Sudan has granted an Iranian firm a licence to explore for gold in the African country, state-linked media said, a sign of strengthening business ties between Khartoum and Tehran.

Sudan state media said in February after a meeting of Sudan's President Omar Hassan al-Bashir and Iran's Mahmoud Ahmedinejad that Khartoum hoped for more investment from Tehran.

Sudan has been trying to attract more investment to explore for gold, which has become the country's main source for dollars needed to fund imports after the loss of most oil production with South Sudan's secession in 2011.

Sudan has said it hopes to produce around 50 tonnes of gold this year, which would potentially make it Africa's third-largest gold miner behind South Africa and Ghana, and push it into the top 15 producers globally.

Sudan has granted an Iranian firm called "Mine an Metals" a licence to explore for gold in River Nile state north of Khartoum, where much of Sudan's gold comes from, the state-linked Sudanese Media Center website said late on Tuesday.

Work would start immediately, it said, without giving more details.

Sudan has handed out hundreds of gold exploration licences, mainly to firms from China, Arab and African countries, Russia and a few Western companies such as Canadians willing to do business with Sudan despite a U.S. trade embargo.

Sudan and Iran enjoy good ties - Bashir and Ahmadinejad have met several times in the past two years - but there are few signs of Iranian firms in Sudan apart from petrol stations run by Iran's state oil firm.

Ties between Sudan and Iran have come under scrutiny in recent months. Two Iranian navy ships visited Sudan in October, days after Sudan accused Israel of bombing a weapons factory in the capital Khartoum. Two more Iranian military ships docked in Sudan's biggest Red Sea port in December.

Israel has declined to comment on the alleged attack on the Yarmouk plant but has accused Sudan of smuggling weapons to the Gaza Strip, which is ruled by the Iranian-allied Palestinian movement Hamas. Khartoum denies this. – Reuters