Global upstream development spending from 2015 to 2020 has declined 22%, or $740 billion, since fourth-quarter 2014. Including cuts to conventional exploration investment, the figure increases to just more than $1 trillion.

"We have seen a large amount of short positions being closed while long positions have been opened," Novak said in reference to speculative bets - shorts - in the market that prices will fall, and the opposite - longs - that they will rise.

"The Kingdom's oil policies are rooted in responsibility, and Saudi Arabia is seeking to maintain that balance while also giving heed to moderate prices for producers and consumers,"

With income falling, the 13 members of the Organization of the Petroleum Exporting Countries (OPEC) posted a combined current account deficit of $99.60 billion in 2015, compared with a surplus of $238.10 billion in 2014.

Russia’s oil industry is “very resilient,” BP Plc CEO Bob Dudley said in St. Petersburg on Thursday. The nation’s resources are competitively priced and floating the currency has been helpful for costs, he said while announcing a new exploration joint-venture with Rosneft.

Brent crude oil prices are forecast to average $43/b in 2016 and $52/b in 2017, $3/b and $1/b higher than forecast in last month's STEO, respectively. West Texas Intermediate (WTI) crude oil prices are forecast to be slightly lower than Brent in 2016 and to be the same as Brent in 2017.

London Brent crude for August delivery was up 9 cents at $51.53 a barrel by 0451 GMT, after settling up 89 cents on Tuesday. It earlier touched $51.55, the highest since Oct. 12.

“We will be very gentle in our approach, so we don’t shock the market in any way,” Saudi Arabia’s new oil minister, Khalid Al-Falih, said before he sat down with his counterparts in Vienna on Thursday. “We are satisfied with the price movement over the last few months and think it will continue to gently edge up without much intervention, assuming that more or less OPEC production stays where it is.”

“We will be very gentle in our approach, so we don’t shock the market in any way,” Saudi Arabia’s new oil minister, Khalid Al-Falih, said before he sat down with his counterparts in Vienna on Thursday. “We are satisfied with the price movement over the last few months and think it will continue to gently edge up without much intervention, assuming that more or less OPEC production stays where it is.”

Russia’s crude production continuing to grow this year by around 100,000 b/d or even slightly above this figure. The growth is supported by investments made in previous years.