If you need to fill up, you might want to hold off until Wednesday.

Tomorrowsgaspricetoday.com says gas prices will be going down 5.7 cents at midnight to 127.8 cents a litre at most stations in the Greater Toronto Area.

Gas watcher Dan McTeague says the drop is due to the decline in the oil and gasoline futures on overseas markets.

The world price of oil plunged nearly $4 in 3 minutes on Monday and the decline on Tuesday morning continued but at a much lower pace.

McTeague also says the drop also reflects that the Canadian oil refineries have a monopoly and have been overcharging Canadians.

"Our Canadian refiners have been padding their margins by as much as twelve or thirteen cents a litre so these prices usually you would see them at five to seven cents above world prices but at twelve and thirteen, these prices have nowhere to go but down," says McTeague.

McTeague says if the refineries don't drop their prices then demand will decrease and they'll be forced to pay a lot to store the unwanted gasoline.