Demand for OPEC's oil will rise to an average 31.65 million b/d in 2016, from 29.90 million b/d in 2015, the producer group said in its latest monthly report.

The escalating rivalry between Saudi Arabia and Iran is intensifying bilateral market competition, which some observers say eclipses in importance Saudi concern over expansion of supply from North America.

The IPO proposal is consistent with the broader direction of economic reform in the kingdom, including state asset sales and market deregulation, Aramco said. Bringing in investors would also strengthen the company’s focus on long-term growth and the prudent management of its reserves, according to the statement.

Iran, which holds the world’s largest gas reserves, was aiming to double its gas production in the next 30 months and to raise its share of global cross-border gas trade from a minuscule one per cent at present to ten per cent at some unspecified future date. In production terms, this means increasing output from 172.6 bcm in 2014 (five per cent of the total world output) to around 350 bcm in 2018-19.

The changes come at a difficult time for the Saudi kingdom, which is still adjusting to last year's leadership transition while also facing pressure from regional rivals like Iran.

“The 800-lb. gorilla in the room, and by that I mean Saudi Arabia, showed it’s power,” said John Kilduff, a partner at Again Capital LLC, a New York-based hedge fund that focuses on energy. “They are on a mission to squeeze out the high-priced producers and aren’t done yet. Things could get very ugly in the second and third quarters for countries like Venezuela and Nigeria and for U.S. exploration companies.”

Government ran a record deficit of nearly 367 billion Saudi riyals ($98 billion) this year, or about 15% of gross domestic product, as low oil prices suppressed revenue, pushing it to cut planned spending by 14% in 2016 amid expectations that income from oil sales will remain under pressure.

The oil-rich kingdom spent hundreds of billions of dollars at home in the past decade to bolster its economy and dole out subsidies that provide cheap energy and food for its 30 million people, as it enjoyed years of high crude prices. But the price of oil has fallen by more than half since the middle of last year, forcing the government to dip into reserves, reassess its spending plans and look for ways to diversify sources of revenue.

The push into Asia comes at a pivotal moment in Saudi Arabia. With oil revenue falling, the kingdom is tightening its belt just as a new king ventures away from the kingdom’s traditionally conservative diplomacy. The International Monetary Fund predicts a budget deficit exceeding 20 percent of economic output this year.

Saudi Aramco, the kingdom's state oil giant, is seeking to borrow $4.7 billion from banks to refinance capital used to build a refinery in collaboration with China's Sinopec, three sources with knowledge of the matter said on Tuesday.