S&P raises Valero's credit ratings to "BBB"

Motivo: debt reduction and management's decision not to pursue additional acquisitions.

An upgrade can cut a company's borrowing costs.

"The ratings on Valero reflect its strong business profile characterized by its position as the largest oil refiner in the U.S., above-average refining complexity, and concentration in key U.S. refining markets," S&P said in statement.