The domination of the Organization of Petroleum Exporting Countries (Opec) over the global energy market has come to an end, according to a former head of the oil cartel.

Abdullah bin Hamad al-Attiyah, also former energy minister of Qatar, told Sky News that the 12-member group that set oil prices for half a century 'has lost its influence'.

"It's over. OPEC cannot play alone. This is why when OPEC met at the last moment they cannot decide it [cutting oil output] because if they will cut there is no meaning it will be the others who will benefit and even increase their production," he said.

In addition, he urged the organisation to collaborate with Russia and reduce global oil production.

Oil rich Saudi Arabia has earlier stated that it would not cut production to arrest the fall in crude prices, even if non-Opec nations have done so, adding that prices would rebound as the market would stabilise on its own.

Saudi oil minister Ali al-Naimi had confirmed that the world's largest oil producer would not cut output following countries outside the Opec. He blamed speculators and a lack of cooperation between non-Opec oil producers for the price slump.

"If they want to cut production they are welcome. We are not going to cut, certainly Saudi Arabia is not going to cut," he said at an energy forum in Abu Dhabi.

Non-Opec producers, "will realize that it is in their interests to cooperate to ensure high prices for everyone," Naimi added.

Crude prices fell about 50% during the last six months, as the supply of the commodity increased significantly amid sluggish demand.

On 27 November, oil cartel Opec said it was keeping its production ceiling unchanged in order to protect the group's market share.

Officials in Iran, Venezuela and Russia have also opined that Saudi Arabia was collaborating with the West to depress oil prices and weaken their governments, which are most hurt by the price slide.

"Talking about such alleged conspiracies against our country is absolutely incorrect and indicates a misunderstanding in some minds. Our economy is based on strictly economic strategies—no more, no less," he said, refuting the argument.

At the energy forum, he stressed on the importance of fossil fuel, which according to him, "Will remain the main source of energy for decades to come."