Industry figures at the annual Asia Oil and Gas Conference also said prices could escalate to $180-$200 a barrel in the next four years.
"It will go to $150 a barrel in the short-term," Fereidun Fesharaki, chairman of oil consultancy Facts Global Energy said on the sidelines of the two-day conference.
"Fundamentally it can go to $180 to $200 a barrel by 2012 and 2013," he said, adding that while high prices have impacted on demand growth, new players have emerged.
"Demand in the US and many key Asian countries has stopped growing," he said in a conference paper. "China, India and the Middle East countries have locked in a demand growth of some one million barrels per day."
Fereidun, the conference chairman, said that price increases in the past two to three months "are all due to huge inflows of speculative money."
Crude oil costs rose in Asia on Tuesday despite a call by the world's leading producer, Saudi Arabia, for talks with consumer nations on soaring prices.
New York's main oil futures contract, light sweet crude for July delivery, gained 63 cents to $134.98 a barrel. The contract slid $4.19 a barrel to close at $134.35 Monday at the New York Mercantile Exchange.
On Friday, the two benchmark crude oil futures contracts hit all-time highs of $139.12 in New York and $138.12 in London.
John Sallee, managing director of clean energy firm World-GTL Inc. said a lack of major oil discoveries and shortage of refinery capacity were pushing oil prices up.
"There is a lot of loose talk of speculation. It is an easy thing to blame. I think the increase in price are due to fundamental issues. There is more oil being consumed and less oil being discovered," he said.
Sallee also said crude oil could hit $150 a barrel in the next one or two months. "In the long run, it will go higher."
Yutaka Kunigo, Japan-based executive officer with Tokyo Gas described prevailing high crude oil prices as "crazy."
"It does not reflect the supply and demand situation. I think speculation by commodities traders is the main reason," he said.