Saudi Arabia and Russia, the world's two largest oil producers, have agreed to co-operate and to freeze oil output at January levels.

The deal is preliminary and does not involve most of OPEC's other major producers - although Qatar and Venezuela are involved.

This is the first agreement between OPEC and non-OPEC producers in 15 years. Saudi Arabia is open the further co-operation.

Saudi Oil Minister Ali Al-Naimi said that this is the "beginning of a process," which could require "other steps to stabilise and improve the market" as the prices bottom out and the global supply glut continues.

Since the lifting of sanctions, Saudi Arabia has resisted pressure to cut its oil production - it has argued that this would result in the country losing market share if it took action without cooperation from its competitors.

"The reason we agreed to a potential freeze of production is simply the beginning of a process ... We don’t want significant gyrations in prices. We don’t want a reduction in supply. We want to meet demand. We want a stable oil price," Mr Naimi told reporters in Tehran.

Russian Energy Minster Alexander Novak said that any cut in oil production in Russia would likely to be dependent on the involvement of more countries.

The exclusion of Iran could be a sticking point - speaking to Bloomberg, Eugen Weinberg head of commodities research at Commerzbank AG in Frankfurt said, "If Iran and Iraq are not a part of the agreement, it’s not worth much - and even then there is still a question of compliance."

Iran ruled out any cuts in production when OPEC last met in December, the country has pledged to increase production.

Negotiations could be complicated by a recent rift between Iran and Saudi Arabia, in early January the beheading of Shiite cleric Nimr al-Nimr by Saudi Arabia led to the cutting of diplomatic ties between the countries.