Brent crude slipped below $69 a barrel on Tuesday, primarily due to a rally in the US dollar in recent sessions, and expectations of rising production levels in the US.
Brent, the global oil benchmark, slid 0.46% to $68.88 a barrel on Tuesday morning in London as the US dollar continued its rally. Nymex West Texas Intermediate, the US benchmark, fell 0.7% to $65.09 a barrel.
On a trade weighted basis, the US dollar remained subdued, but against both the euro and the yen - two of the world's biggest oil importers - the dollar has gained about 4% during the past three weeks.
Because oil on global markets is priced in dollars, a rally in the US currency makes the commodity more expensive to buy from countries that must also organise foreign exchange transactions for their purchases.
"A key driver in the weakness of crude has been somewhat of a recovery in the dollar," said Hamza Khan, head of commodities strategy at ING.
US oil rig count
Hamza also pointed to a large week-on-week increase in the US oil rig count - a key metric in determining potential rates of future output in the US.
The Baker Hughes US oil rig count rose to 947 on the 26 January, that was up 11 on the previous week, but up a massive 235 on the same week a year ago, when the price of Brent crude was sitting around the $56 a barrel mark.