Saudi Arabia 's national oil company Aramco will "relax" production at some of its oldest and largest oil fields as new ones come onstream, the company's Chief Executive Khalid al-Falih is cited as saying by the Financial Times Tuesday.

The "lower plateau" of production at the fields, including Ghawar and Abqaiq, will ensure they continue producing into the next century, said Mr. al-Falih.

He denied the ratio of water to oil produced at these fields was rising--an indication they could be in steep decline. The water content at the fields is stable at 30%, he said.