NEW YORK, Oct. 7 (UPI) -- Crude oil prices rose overnight on the New York Mercantile Exchange, climbing toward $84 per barrel, after two European banks left monetary policy unchanged.

The Bank of England kept its lending rate at 0.5 percent. The European Central Bank left lending at 1 percent. Currency rates, which shifted when the Bank of Japan lowered its overnight lending rate to zero to 0.1 percent this week, have given commodity prices a boost, as the dollar continues to weaken.

The dollar index, at nearly 87 in June, fell to 77.18 Thursday, below Wednesday's 77.44.

The index measures the dollar against six major currencies with a pro-rated formula.

On Thursday morning, the price of light, sweet crude for November delivery added 54 cents to $83.77 per barrel. Heating oil prices added 0.86 cents to $2.3164 per gallon. Reformulated gasoline prices added 1.73 cents to $2.1732 per gallon.

Henry Hub natural gas prices shed 8.2 cents to $3.785 per million British thermal units.

At the pump, the national average price of unleaded gasoline rose to $2.768 per gallon from Wednesday's $2.751, AAA said.