JEDDAH /BERLIN  - Oil powers and consumer nations haggled Saturday over who is to blame for the spectacular rise in crude prices, as they prepared for a summit in Saudi Arabia on the global energy crisis. Amid growing pressure for international action as prices speed toward $140, the industry was rocked by more bad news when a Nigerian rebel group warned all foreign workers to leave the country or face attack. The Jeddah Energy Meeting was to consider ways of ending oil price pressures, which have fuelled global inflation. Growing demand and the need for greater investment in refining have been highlighted, but some nations want the summit to blame the price rises on market funds buying oil futures. And a working paper for the summit's final declaration, obtained by AFP, calls for action to "improve the transparency and regulation of financial markets through measures to capture more data on index fund activity and to examine cross exchange inter-actions in the crude market." A senior international energy official involved in the summit called the document "highly controversial" because of the attack on markets. The document says index funds and other investors have "unrealistic assessments" of the future value of oil. The official said the attack may be toned down in the final document because of opposition from the US and other major industrial powers. Major oil producing powers have sought to divert consumer calls for greater production, even though Saudi Arabia was expected to offer to pump an extra 200,000 barrels a day at the summit. German Economy Minister Michael Glos has called for a quick increase in oil supplies. "We need more oil in the world market quickly in order to stop the spiralling prices at the gas pumps," which have passed a "limit" which consumers cannot bear, the minister wrote in an article to appear in the Sunday newspaper Bild am Sonntag. "Transparency in the international oil markets must be improved. It is the only way to get out of this speculative morass," he wrote. Increased production is is opposed by many oil powers. Organisation of Oil Exporting Countries president Chakib Khelil asked Friday, "just because car and computer prices were high, would one ask their producers to make more?" The summit document calls for improved information gathering by groups such as OPEC, the IEA and the International Energy Forum (IEF) "to improve transparency." It also appeals for an assessment of "the impact of financial markets on the level, volatility of oil prices which can be used to better understand the market situation." The draft says increased refining capacity is needed, with new construction having been shackled by "constrained refining investment, environmental standards, cost inflation and stringent laws and regulations, resulting in poorer refining returns." British Prime Minister Gordon Brown, who will be the only major Western leader at the summit, has insisted he was not going to simply urge increased supply but urge producer countries to invest more in renewable energy. "I am going to Saudi to see if we can get a new deal between oil producers and the consumers where oil producers will invest in countries like ours, and oil consumers like us with good companies, with good technology and skills can invest in the oil-producing countries," he told The Guardian newspaper in an interview published Saturday. "Where we can make credible commitments and the world can see we will reduce our dependence on oil and we will get demand and supply back into balance." Brown said the world was going through "the biggest of all three oil shocks" which was "the downside of globalisation". He predicted that "the world is going to have to build 1,000 nuclear power stations." The meeting is also to be attended by Chinese Vice President Xi Jinping and US Energy Secretary Samuel Bodman.