Somali pirates have released an Iranian-chartered ship seized in November and said on Saturday they were hopeful a Ukrainian ship loaded with tanks would be freed soon.

Iran's biggest shipping firm said Delight, a cargo ship ferrying 36,000 tonnes of wheat to Iran from Germany, was released on Friday, the same day a Saudi tanker was freed after a $3 million ransom was parachuted onto its deck.

Somali pirates caused havoc in one of the world's busiest shipping lanes in 2008, hijacking dozens of ships including the Hong Kong-flagged Delight and Saudi supertanker Sirius Star with its $100 million worth of crude.

Pirates holding a Ukrainian cargo ship with 33 T-72 tanks and other weapons on board said they might lower their ransom demands and release the MV Faina in the coming days.

Islamic Republic of Iran Shipping Lines (IRISL), which chartered Delight, said it was going to Iranian waters with its 25 crew. The company did not say whether a ransom had been paid.

'Nothing has happened to the cargo. The cargo has not been touched,' said an IRISL official who declined to be named.

Iran said last month it had dispatched a warship to the Gulf of Aden to protect Iranian vessels.

On Friday, pirates freed Sirius Star, whose capture in November drew attention to a surge in piracy off Somalia which worsened dramatically last year as an Islamist insurgency fuelled chaos onshore.

The MV Faina, seized in September, also made headlines. Although the cargo was destined for Kenya's Mombasa port, Washington said the weapons were bound for south Sudan.

Ransoms

'Since negotiations with the owners and Somali brokers are under way at the moment, we may reduce our demands and release the ship in the coming days when the bargaining is completed,' said Sugulle Ali, spokesman for the pirates aboard the ship.

Hussein Ali, an associate of the pirates, told Reuters the hijackers wanted $5 million, down from an initial $20 million demand, but the owners were holding out for less.

'Negotiations are going well and we hope this time a fruitful deal will be struck,' he said.

Somalia's interim president Sheikh Aden Madobe said on Saturday as long as ransoms were paid, piracy would persist and the problem must be tackled on land.

'It is the ransoms that are encouraging these pirates to continue their operations, and that contributes to the problem,' he told Reuters in an interview during a visit to Kenya.

'Everyone sees young, poor and unemployed men in their rural villages earning millions of dollars from a hijacked ship, building their own houses and buying new cars. That encouraged many people to join the pirates,' he said.

Gunmen released a Turkish cargo ship, the MV Yasa Neslihan, earlier this week after its owners paid a ransom.

Piracy in the busy Gulf of Aden and Indian Ocean shipping lanes has raised insurance premiums, prompted some owners to go round South Africa instead of through the Suez Canal and brought an unprecedented deployment of warships to the region.

The U.S. Navy said on Thursday it would launch a force to combat Somali piracy, an offshoot of an earlier mission. Chinese warships also began anti-piracy patrols off Somalia this week.-Reuters