Oil prices continued to rise Wednesday despite data showing crude inventories unexpectedly grew last week.

Crude for July delivery closed up 73 cents at $77.67 US a barrel on the New York Mercantile Exchange.

TSX energy sub-index, 1-month chartTSX energy sub-index, 1-month chart

On Tuesday, the contract rose $1.82 to settle at $76.94.

The U.S. Energy Department's Energy Information Administration said crude supplies increased by 1.7 million barrels last week. Analysts had been looking for a decline of 1.75 million barrels.

The EIA said gasoline demand rose but U.S. refineries operated at 87.9 per cent of their capacity, down 1.2 percentage points from the previous week.

Traders bought on that news, assuming that refineries would have to make up for the draw on gasoline supplies by increasing their demand for crude in the coming weeks.

Oil prices fell below $70 US a barrel last month amid worries that Europe's debt crisis would derail the global economic recovery and hurt demand for crude.