sentences:  Since 1998, Western diplomats and intelligence agencies have long believed that an agreement exists in which Pakistan would sell Saudi Arabia nuclear warheads and its own nuclear technology should security in the Persian Gulf deteriorate.Both countries have sharply denied the existence of such an agreement.In 2003, globalsecurity.org reported that Pakistan and Saudi Arabia had entered a secret agreement on nuclear cooperation providing Saudi Arabia with nuclear weapons technology in return for access to cheap oil for Pakistan.