The National Iranian Oil Company (NIOC) is set to increase production from all oilfields this year and can reach its pre-sanctions output capacity of 4 million barrels per day if there is sufficient market demand, a top Iranian oil official told a newspaper on Wednesday.

Iran and six major world powers reached a landmark nuclear deal on Tuesday, clearing the way for an easing of international sanctions on Tehran and higher oil exports.

"We want to reach to our pre-sanctions capacity. We tested a production increase in the main oilfields last year," Roknoldin Javadi, NIOC managing director told Iran's Shargh newspaper.

"This year we have been ordered to increase production in all fields."

He said it might take six months to a year until Iran can claim its previous position in the global oil market.

"Iran's oil production capacity was 4 million barrels a day before the sanctions. We can reach that if there is demand in the market," Javadi told Shargh.

Iran can increase oil output by 500,000 to 600,000 bpd and the main market targeted for the extra supplies will be South East Asia, he added.

Oil Minister Bijan Zanganeh said last month that Iran was aiming to add 500,000 barrels per day (bpd) to production within two months of easing Western sanctions that have halved shipments in recent years, and as much as 1 million bpd in six to seven months.

But years of underinvestment mean Iran may struggle to get its oil industry anywhere near full potential, analysts say. It will also take time for Tehran to raise output as nuclear inspectors verify Iran's compliance with the terms of any deal and sanctions are slowly removed. - Reuters