Brent North Sea crude for delivery in December sank 25 cents to USD 82.70 a barrel in late afternoon deals in London.
US benchmark West Texas Intermediate for December shed 75 cents to USD 77.93 a barrel compared with yesterday's closing level.
"Crude oil (traded) lower on the combination of Draghi talking the dollar up and OPEC cutting the forecast for the amount of crude oil it will need to supply due to rising shale oil production," said Saxo Bank analyst Ole Hansen.
The euro meanwhile tumbled against the dollar after Draghi revealed the ECB's readiness to take further steps to stimulate eurozone economic growth and counter the threat of deflation.
"The governing council has tasked ECB staff and the relevant Eurosystem committees with ensuring the timely preparation of further measures to be implemented, if needed," Draghi told reporters.
The news sent the European single currency sliding as low as USD 1.2396, its lowest level since late August 2012.
Back in Vienna, the 12-nation Organization of the Petroleum Exporting Countries (OPEC) released its latest assessment of the global oil market.
"Crude oil prices came under renewed pressure today as OPEC cut its oil price forecasts," said Sucden analyst Myrto Sokou on today.
