Any amendment requires the approval of three-quarters of the states, plus a two-thirds majority in both houses of Congress.

ECONOMIST: Gay marriage

The European Union (Approval of Treaty Amendment Decision) Bill ratifies the creation of a new European bailout agreement between eurozone countries, from which the UK is exempt.

BBC: Alexander lambasts 'imperial delusion' of coalition

Among other prerogatives, the Conference of States Parties to the International Convention against Doping in Sport is also responsible for the review and approval of any amendment to the Convention.

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