Gulf Arab oil ministers, striving to boost sagging oil prices, united on Monday in calling for a higher OPEC output ceiling that included renegade Iraq.

But the ministers of the six-nation Gulf Cooperation Council, responsible for one-fifth of the non-Communist world's oil production, said their offer depended on all OPEC members sticking to quotas.One oil industry analyst said the gulf ministers' proposals could form the basis of a new Organization of Petroleum Exporting Countries output pact when the cartel's price and long-term strategy committees meet in Madrid on Thursday to debate ways of halting the slide in oil prices.

"(GCC) members are willing to abide by output levels agreed upon by OPEC within a production ceiling of 17.429 million barrels per day (bpd) for all OPEC or any higher ceiling agreed upon by the organization," a statement at the end of a one-day oil ministers meeting in Riyadh said.

Twelve of the 13 OPEC states have an official output ceiling of 15.06 million bpd.

Iraq has been out of the pact since 1986 when its demands for quota parity with Iran's 2.369 million bpd was refused. It currently produces around 2.7 million bpd.

The Riyadh plan makes it clear that the four key GCC players in OPEC - Saudi Arabia, Kuwait, the United Arab Emirates and Qatar - want to include Iraq in OPEC's quota.

The GCC oil ministers, who include non-OPEC Bahrain and Oman, said if OPEC decided to raise the output ceiling higher, it should be distributed proportionately.

Oil traders in the Gulf said the GCC proposal, which still had to be approved by OPEC and Iran and Iraq, was a positive factor for the depressed oil market as it indicated more unity among OPEC members.