The oil ministry in OPEC member Kuwait on Monday denied that it has started a joint oil development with neighboring Iran.
"There is no cooperation between the two sides in this regard," said the ministry assistant undersecretary for technical affairs Ali Sabt, cited by the official KUNA news agency.
Sabt was commenting on a report by Iranian official media last week which quoted an Iranian oil official as saying the two countries have started work on developing a joint oilfield.
The Arab Gulf state of Kuwait and non-Arab Iran have been involved in unsuccessful talks to resolve a decades-old dispute over a maritime border area that is rich with natural gas.
The dispute dates back to the 1960s when Iran and Kuwait awarded offshore concessions to the former Anglo-Iranian Petroleum Co, now part of BP, and Royal Dutch/Shell that overlap in the northern part of the Dorra field.
Recoverable gas reserves from Dorra are estimated at some 200 billion cubic metres (seven trillion cubic feet).
The two countries also failed to implement a seven-billion-dollar 25-year deal signed in 2005 to supply Iranian gas to Kuwait.
Ties between the two countries strained after a Kuwaiti court in May sentenced three people to death and two others to life in prison after convicting them of being members of an Iranian spy ring.