"The ball is in the court of the EU. They have presented different proposals, we will see if they materialise," said the head of Iran's Atomic Energy Organisation, Ali Akbar Salehi.

He was speaking after meeting European Union Energy Commissioner Miguel Arias Canete, the first high-level Western official to visit Iran since the US withdrew from the 2015 nuclear deal between Tehran and world powers earlier this month.

Canete called the nuclear deal "fundamental for peace in the region" as he outlined EU plans to continue oil and gas purchases and protect European companies from US sanctions as they are phased in over the next six months.

He also had detailed talks with Oil Minister Bijan Namdar Zanganeh on practical solutions, which he said included plans for direct payments between central banks and state-backed insurance for shipments.

A group of experts later met their Iranian counterparts to hash out the details.

Zanganeh said there were no plans to change Iran's pattern of oil exports, which amount to 3.8 million barrels per day, with 70 percent going to Asia and 20 percent to Europe.

Salehi acknowledged Europe's efforts to protect trade but said: "We want tangible results, otherwise we take our own decisions. I personally don't want to see such decisions being taken."

Iran has threatened to resume industrial uranium enrichment "without limit" unless its interests are preserved by the remaining parties to the deal, which also include China and Russia.

Salehi said the Iranian people had lost trust in the nuclear agreement and that if trade benefits were not protected "they will lose more confidence... and we will be forced to leave."

- EU firms eye exit -

Despite vows by European leaders to protect EU firms from US sanctions, several companies -- including France's Total and Holland's Maersk -- have already said it will be impossible to stay unless they receive explicit exemptions from Washington.

On Friday, French energy giant Engie said it would begin pulling out of all projects in the Islamic republic in order to avoid being hit by US sanctions.

"For sure there are clear difficulties with the sanctions," Canete said at a press conference alongside Salehi.

"We will have to ask for waivers, for carve-outs for the companies that make investments."

Canete was due to meet Foreign Minister Mohammad Javad Zarif on Sunday.

Iran's trade with the European Union is worth around 20 billion euros a year, evenly split between imports and exports.

Oil accounts for some 90 percent of EU imports from Iran, going primarily to Spain, France, Italy, Greece, the Netherlands and Germany.

Iran has the world's fourth-biggest oil reserves and second-largest gas reserves.

But it has only finalised two major energy deals since the sanctions were lifted: Total's $4.8-billion South Pars 11 project with the China National Petroleum Corporation, and a $740 million deal with Russia's Zarubezhneft to develop the Aban and Paydar oilfields.

Analysts say Iran's hardliners remain wary of foreign involvement in the energy sector, and the Revolutionary Guards have sought to maintain their privileged position in major projects -- delaying negotiations with Western firms.

Russia and China are less vulnerable to economic pressure from Washington, and analysts say they could benefit from Europe's difficulties in Iran.

csg-pg/par

A.P. MOELLER-MAERSK

TOTAL