Current Kirchner Administration policies and difficulty in enforcing contractual obligations had been blamed for this modest performance.

In challenging this argument, Solicitor General Waxman told the justices that it ran counter to the court's "completely unbroken practice of enforcing obligations equally whether they arise under statutes or regulations."

Mr. Waxman told the court that the case had "very, very broad ramifications" beyond the civil rights laws for enforcing "regulatory obligations against the states," for example, under the federal Medicare statute and regulations.

"Both involved the courts enforcing well-known, longstanding obligations of fair play and fundamental constitutional protections."

The Court disagreed: "The President has an array of political and diplomatic means available to enforce international obligations, but unilaterally converting a non-self-executing treaty into a self-executing one is not among them."

They also seek to overcome the difficulties in enforcing positive obligations, such as such as an obligation to keep property in good repair, in freehold land.

The directory was created under a 1996 law to help enforce child-support obligations.

In practice reliance is placed on s.33 of the Local Government (Miscellaneous Provisions) Act 1982 which provides the local authority with an express power to enforce positive obligations against successors in title.

In mercantile contracts, 'broadly speaking time will be considered of the essence', and so it is highly likely the courts will enforce obligations to the letter.

FDI volume remained below the regional average as a percent of GDP even as it recovered, however; Kirchner Administration policies and difficulty in enforcing contractual obligations had been blamed for this modest performance.