UAE-based Crescent Petroleum is seeking international arbitration for the failure of Iran's state oil firm to fulfil a gas export contract, Crescent said in a statement on Wednesday.

The National Iranian Oil Company (NIOC) has yet to complete testing facilities at its offshore Salman field that should have pumped the Islamic Republic's first gas exports to the United Arab Emirates in December 2005.

'We did not want to take this step.... (but) some of our customers have lost patience and are demanding performance, leaving us with no option but to seek a determination on the legal obligation of NIOC to deliver gas, and also to seek an indemnity from NIOC in respect of the claims of our customers,' Crescent said in the statement.

Statements by some NIOC officials had shaken Crescent customers' confidence in NIOC's commitment to the contract, the UAE firm said.

Iran's Oil Minister Gholamhossein Nozari has threatened to take the gas back to the mainland if a new agreement cannot be reached on price. Crescent has said the contract to deliver gas to the UAE already has an agreed price and was internationally binding.

NIOC and Crescent signed the 25-year contract in 2001, with a price linked to oil. As oil rallied in following years, some officials and politicians in Iran called for a revision to the price formula. They have blamed the price dispute for the delay.

Crescent says the two sides provisionally agreed on a revised price in September last year, but that it has heard nothing from NIOC on the price since.

"We had positive negotiations over several months with the appointed representative of the president of Iran, in the full presence of NIOC officials," Majid Jafar, executive director at Crescent, told Reuters.

"These concluded with agreement in principle last September but since that time the agreed follow-up from NIOC has not taken place."

NIOC has yet to give Crescent a start date for exports, even though contractors working on the project have said they expect facilities to be ready later this summer, Crescent said.-Reuters