RIYADH, March 22 (Reuters) - OPEC will not take sole responsibility for propping up the oil price, Saudi Arabia's oil minister said on Sunday, signalling the world's top petroleum exporter is determined to ride out a market slump that has roughly halved prices since last June.

Last November, Organization of the Petroleum Exporting Countries kingpin Saudi Arabia persuaded members to keep production unchanged to defend market share.

The move accelerated an already sharp oil price drop from peaks last year of more than $100 per barrel that was precipitated by an oversupply of crude and weakening demand.

Since the oil price collapse, top OPEC exporter Saudi Arabia has said it wants non-OPEC producers to cooperate with the group. But Saudi oil minister Ali al-Naimi said on Sunday that plan had so far not worked.

"Today the situation is hard. We tried, we held meetings and we did not succeed because countries (outside OPEC) were insisting that OPEC carry the burden and we refuse that OPEC bears the responsibility," Naimi told reporters on the sidelines of an energy conference in Riyadh.

"The production of OPEC is 30 percent of the market, 70 percent from non-OPEC ... everybody is supposed to participate if we want to improve prices."

Earlier, OPEC governor Mohammed al-Madi said it would be hard for oil to reach $100-$120 per barrel.