New York's main contract, light sweet crude for delivery in February, shed nine cents to $94.05 a barrel and Brent North Sea crude for February delivery dipped nine cents to $111.79.
Crude markets slipped after most indices on Wall Street edged lower and Obama's warning shook market sentiment, IG Markets said in a report.
"On Wall Street, the January bull market took a backward step.... Comments by President Obama also did little to fuel the bulls," the report stated.
Obama issued a stern warning to Republicans on Monday not to use the debt limit as a bargaining chip.
"To even entertain the idea of this happening, of the United States of America not paying its bills, it is irresponsible, it is absurd," Obama said, repeating his demand for a debt limit rise.
Republicans reacted swiftly, essentially ignoring Obama's demand to de-couple the spending debate from the debt ceiling and giving every indication that the face-off will continue.
The United States ran up against its current debt limit at the end of 2012, but the government is using "extraordinary measures" to extend the limit until late February.
Congressional refusal to raise the debt limit beyond its current level of $16.4 trillion could delay key government payments in the world's largest economy and oil consumer, sending markets "haywire," Obama warned.
