West TX Oil at $59.50 on High OPEC Output

Oil prices closed modestly lower on Monday, retreating from the sharp rally of the previous session, on the impact of a strong dollar and worries of stubbornly high supplies as OPEC prepared to meet this week to stick to production targets.

U.S. crude settled down 10 cents, or 0.2 percent, at $60.20 a barrel, while front-month Brent crude slipped 75 cents to $64.80 a barrel.  The Organization of the Petroleum Exporting Countries pumped at a two-and-a-half year high of 31.22 million barrels of oil per day (bpd) in May, a Reuters monthly survey showed.

The boost from OPEC puts output further above its target of 30 million bpd, underlining the focus of top exporter Saudi Arabia and other key members on market share.