The chief executive of Exxon Mobil Corp. is telling Congress that the Gulf oil spill wouldn't have happened if BP had properly designed its deepwater well, followed procedures, trained its employees and conducted adequate tests.

Exxon's Rex Tillerson was testifying Tuesday on Capitol Hill with other oil company executives before the House Energy and Commerce Committee. He told lawmakers the 1989 Exxon Valdez tanker spill changed the way his company operated.

In prepared testimony, Tillerson wrote that Exxon doesn't go ahead with operations "if we cannot do so safely."

Tillerson's assertion drew little sympathy from lawmakers. They complained that oil spill response plans of the nation's five largest oil companies are nearly identical — and inadequate.