By Doug Palmer

WASHINGTON (Reuters) - The U.S. trade deficit widened more than expected in April as the price of imported oil hit a record, pushing overall imports to an all-time high, a Commerce Department report showed on Tuesday.

The monthly trade gap grew 7.8 percent to $60.9 billion, its biggest one-month gain since September 2005, despite a healthy rise in exports to a record $155.5 billion (79.6 billion pounds).

The wider deficit was due mostly to higher average prices for imported oil, which rose $6.96 per barrel in April to a record $96.81. Imports from Saudi Arabia, Venezuela and other members of the Organization of Petroleum Exporting Countries hit a record $20.9 billion.

Oil prices hit a record high near $140 per barrel on Friday, suggesting imported oil costs will continue to climb. Even so, trade is expected to remain a source of strength for the economy, which has been buffeted by a severe housing downturn and a credit crisis.

"We expect foreign trade to add more than 1 percentage point to GDP growth in the second quarter, a crucial contribution that helps keep overall growth just above zero," said Nigel Gault, chief economist at Global Insight.

Overall U.S. imports of goods and services reached a record $216.4 billion in April as they showed their biggest one-month gain since November 2002. Although oil accounted for much of the increase, imports of autos and capital goods bounced back after dropping in March.

Even with the run-up in oil prices, the U.S. trade deficit is $4 billion lower than it was in the first four months of 2007, U.S. Commerce Secretary Carlos Gutierrez noted in an interview.

"Without the impact of petroleum, the year-to-date deficit would have improved by over $50 billion. We're talking about one of the best eras we've ever had in our history for exports," Gutierrez said.