Iraq's Oil Ministry says the country's crude oil exports dropped by 2.2 percent from April to May due to increased domestic demand.

Ministry spokesman Assem Jihad said Sunday that oil exports averaged 2.452 million barrels a day in May, down from an average of 2.508 million barrels a day in April.

Jihad says Iraq earned $8 billion from oil exports in May, compared to $8.8 billion in April.

Domestic demand in Iraq usually increases during the hot summer months.

Iraq holds the world's fourth largest oil reserves, some 143.1 billion barrels. Oil income makes up nearly 95 percent of the government's revenues.