Kuwait and Saudi Arabia have "exclusive rights" in a gas field in the Persian Gulf disputed with Iran, Kuwait Oil Minister Saad Al Barrak reiterated on Sunday.

He also repeated earlier calls on Iran to validate its claim to the field by demarcating its own maritime borders first.

Iran has previously said it has a stake in the field and called a Saudi-Kuwaiti agreement signed last year to develop it "illegal".

"Until this moment, this is an exclusive right of Kuwait and Saudi Arabia in the Durra field, and whoever has a claim must start demarcating the borders. And if it has a right, it will take it according to the rules of international law," Al Barrak said in an interview with Saudi state-run Al Ekhbariya television.

"The other side has claims that are not based on a clear demarcation of the maritime borders," he added, referring to Iran.

Iran claims any development without its consent breaks international laws, and insists that 40 percent of the field is located in its territorial waters.

Al Barrak's comments echo those of Saudi Arabia, which said last week that the kingdom and Kuwait exclusively own natural wealth in the Gulf's maritime "Divided Area".

Saudi Arabia also renewed its call to Iran to start negotiations with Riyadh and Kuwait on the demarcation of the eastern border of the area, Saudi state news agency SPA said.

Called Arash in Iran and Durra or Dorra by Saudi Arabia and Kuwait -- the offshore field was discovered in 1967 and is estimated to have a total proven reserves of around 310 million barrels of oil and 20 trillion cubic feet of gas.

With reporting by Reuters