Saudi Arabia is ready to make up for any shortfall in Iran's oil exports under new Western sanctions over the Islamic republic's nuclear programme, the kingdom's oil minister said.

The comments, to be aired later Monday, were made in an interview with CNN television's Global Exchange program recorded at the weekend before Saudi Arabia's regional arch-rival Iran warned Gulf states against such actions.

"We are idling now between 9.4 and 9.8 (million barrels per day)... so we have substantial spare capacity (to produce) 12.5" million bpd, said the Saudi oil minister, Ali al-Naimi.

"I believe we can easily get up to 11.4, 11.8 (million bpd) almost immediately, in a few days. Because all we need is to turn valves. Now to get (the rest) we probably need about 90 days," he said.

On Sunday, Tehran's representative to OPEC, Mohammad Ali Khatibi, was quoted as saying that if Iran's Arab neighbours compensate for a looming EU ban on Iranian imports, "we would not consider these actions to be friendly."

"They will be held responsible for what happens" in that case, he said, adding ominously: "One cannot predict the consequences."

The warning comes as Iran is being hammered on several fronts over its nuclear programme, which it is defiantly expanding.

Western sanctions are being ratcheted up, shaking Iran's oil-dependent economy.

They are also threatening to close the Strait of Hormuz in the Gulf if extra sanctions bite, cutting off the transport of 20 percent of the world's oil.

But "I personally do not believe that the Strait, if it were shut, will be shut for any length of time," said Naimi. "The world cannot stand for that."

Senior International Atomic Energy Agency officials are to visit Iran on January 28 to discuss suspicions over Iran's activities that were crystallised in an IAEA report two months ago.

But just before that, on January 23, EU foreign ministers are expected to announce additional sanctions on Iran targeting its oil exports and possibly also its central bank.

They would add to US sanctions signed into law last month by President Barack Obama that bar foreign companies from doing business in America if they have dealings with Iran's central bank.

Iran exports around 2.5 million barrels of oil per day, bringing in up to $100 billion last year.

Iran-Saudi ties are poor, especially after US allegations last October that a thwarted plot to assassinate the Saudi ambassador in Washington was hatched in Tehran.