In March, the US dollar continued to fall sharply versus major currencies, including the euro, the Japanese yen, the Pound sterling and the Swiss franc, said the report.
The current exchange rate between the euro and the US dollar has surpassed 1.59 and is approaching 1.60. Some analysts even predict a possible future exchange rate of 1.65.
Experts, therefore, point out that only when expectations about the US dollar's depreciation completely break down can international oil prices truely step on a downward track.
However, some experts say other aspects besides the weak dollar are also responsible for pushing oil prices up dramatically and they would continue to wield an influence on international oil price trends.
Insufficient supply,strong demand
The balance of international crude oil supply and demand remains tight.
According to OPEC's latest monthly report, demands from the Organization for Economic Cooperation and Development (OECD) countries will slightly decline, while demands from non-OECD nations, including some in Asia, the Middle East and Latin America, will stay strong, leading to a growth of global demand for crude oil.
OPEC expects an additional daily average output growth of 1.2 million barrels or a daily average oil output of 87 million barrels in 2008.
The OPEC output quota this year will be less than 32 million bpd and non-OPEC output would be about 50.3 million bpd, the report added.
Although OPEC's actual production will be higher than the quota, analysts are still pessimistic about the demand-supply imbalance in the international market.
OPEC unwilling to increase output
OPEC tends to limit production to maintain current prices.
Its proven oil reserves comprise nearly 80 percent of the global total, with its crude oil output accounting for about 40 percent of the world. It therefore plays a decisive role in stabilizing supply and demand on the international market.
However, confronted with rising oil prices, OPEC has thrice declined to increase output since last December. It also insists that the economic recession in the United States will influence global economic growth and result in a decline of world demand for crude oil.