Saudi Arabia and other producers with oil to spare could agree to raise output at an emergency meeting of energy powers this weekend.
But OPEC countries say speculation, not supply, is behind high prices.
Riyadh has summoned energy producers, consumers and chief executives from big oil firms to meet tomorrow.
The oil price has more than doubled in a year to almost $140 a barrel, triggering protests from Brussels to Bangkok over record fuel costs that threaten the world's economy.
Saudi Arabia has said it will raise its crude output to 9.7m barrels per day in July.
The kingdom, the world's biggest oil exporter, has a policy of keeping a cushion of spare capacity and has said other OPEC members that can bring on extra production quickly would also discuss boosting output to try to tame the oil rally.
Looking to the longer term, Saudi Arabia may consider increasing its capacity beyond an existing goal of 12.5m barrels per day by the end of next year.
The two other OPEC members with some extra capacity are the United Arab Emirates and Kuwait.
Another OPEC delegate said it was not yet clear whether they would join in any output rise.
While consumer nations have said an OPEC output rise would help to calm runaway oil markets, OPEC member countries have repeatedly blamed factors including speculation, a weak dollar and political instability.
Tomorrows meeting is also expected to look at whether speculation is responsible for current price levels and what can be done about it.
Investment funds have pumped billions of dollars into oil and other commodities as they seek to diversify holdings and flee poorly performing asset classes.
US regulator the CFTC, under pressure from lawmakers, has announced a task force to explore commodity activity. It made public this week a deal with its British counterpart to limit trading on oil futures on the London-regulated ICE exchange.
While Riyadh wants action from consumer governments to rein in speculators, Western leaders, including US President George . Bush, have lobbied heavily for more Middle Eastern crude.
Saudi Arabia's King Abdullah will open the meeting tomorrow followed by an address by Britain's Prime Minister Gordon Brown, the highest-level foreign dignitary to attend.
