What is the standard of review for a motion alleging that the federal government breached a plea agreement by filing a section 5K1.1 motion?

The standard of review is unclear. See United States v. Salemo, 81 F.3d 1453, 1460 (9th Cir.) (reviewing alleged breach of a plea agreement for clear error), cert. denied, 117 S.Ct. 436 (1996). But see United States v. Diamond, 53 F.3d 249, 252 (9th Cir.) (reviewing alleged breach of a plea agreement de novo), cert. denied, 116 S.Ct. 326 (1995). We need not resolve this issue, because under either standard, the government did not violate the plea agreement, and thus the district court properly declined to order the government to file a section 5K1.1 motion.