The International Court of Justice ruled Monday that the United States defied its order last year when authorities in Texas executed a Mexican convicted of rape and murder.
The U.N.'s highest court said the U.S. remains obliged to review the cases of about 50 other Mexicans on death row because they were denied access to their consulate after they were arrested.
But it rejected Mexico's request that Washington guarantee that each case will be reviewed and reconsidered.
Both Mexico and the United States said they were satisfied with elements of the decision.
"It was a mixed result," said John Bellinger III, the legal adviser to the U.S. State Department.
He said the court refused Mexico's main request to spell out the U.S. obligations toward the arrested Mexican nationals, which likely would have led to heightened demands on the U.S. courts. But he was "disappointed" the tribunal declined to acknowledge efforts by the Bush administration to comply with international law and with the court's order.
The Mexican government applauded the ruling in a statement and urged U.S. President-elect Barack Obama to "take concrete actions" to comply with the ruling and "respect the rights of all Mexican nationals." Obama takes office Tuesday.
The judgment ended a five-year cascade of proceedings in the wake of a 2004 decision by the same court that the U.S. had violated an international treaty by failing to advise 51 Mexicans of their consular rights. The court required that each case be reviewed to determine whether the lack of diplomatic access could have affected the outcome of their cases.