Relations with the Bulgarians worsened. It is likely that Nikephorus bribed the Kievan Rus' to raid the Bulgarians in retaliation for them not blocking Magyar raids. This breach in relations triggered a decades-long decline in Byzantine-Bulgarian diplomacy and was a prelude to the wars fought between the Bulgarians and later Byzantine emperors, particularly Basil II. Svjatoslav and the Rus struck Bulgaria in 968 but they had to retreat to save Kiev from a Pecheneg invasion.