The price of oil is quoted in US Dollars which means that a component of its price is due to fluctuations in the US currency.
Yesterday, the Dollar weakened against both Sterling and the Euro and this was enough to cause the price of both Brent crude and US light crude by more than $3 a barrel. Brent closed at $75.68 and US light crude ended the trading session at $77.01.
The other side of the oil price equation is demand and analysts believe that the price may fall back on weak demand since the global recovery remains fragile and supply is plentiful.
Output from members of the OPEC oil cartel is increasing and many of the consuming nations have healthy inventories at the moment, so the spike could be short-lived.
Oil Price Rises On Perceived Dollar Weakness
DailyForex.com