Benchmark crude for August delivery slipped eight cents to $103.14 on the New York Mercantile Exchange.
Oil was pushed higher last week by worries turmoil in Egypt could disrupt shipments through the Suez Canal and a report showing robust job growth in the U.S. in June.
Later this week, the U.S. Energy Department releases its weekly report on supplies of crude oil and petroleum products, the U.S. Federal Reserve releases minutes of its recent policy meeting and OPEC issues its monthly update on the oil market.
A large decline in U.S. supplies, or signs that OPEC decreased output last month could boost prices, analysts say. Additional insight into the Fed's thinking on monetary policy should also influence trading.
In the U.S., the average price for a gallon of gasoline was unchanged at $3.47. That's down 16 cents from a month ago, but nine cents more expensive than at this time last year.
Brent crude dropped 29 cents to $107.43 a barrel on the ICE futures exchange in London.
In other energy futures trading on the Nymex:
— Wholesale gasoline dropped one cent to $2.88 per gallon.
— Natural gas rose 12 cents to $3.74 per 1,000 cubic feet.
— Heating oil fell one cent to $2.98 per gallon.
(TSX:ECA, TSX:IMO, TSX:SU, TSX:HSE, NYSE:BP, NYSE:COP, NYSE:XOM, NYSE:CVX, TSX:CNQ, TSX:TLM, TSX:COS.UN, TSX:CVE)