<P> The power of the purse's earliest examples in a modern sense occurred in the English Parliament, which gained the exclusive power to authorise taxes and thus could control the nation's cash flow . Through this power, Parliament slowly subverted the executive strength of the crown; King Charles II was limited in his powers to engage in various war efforts by a refusal by Parliament to authorise further taxes and by his inability to secure loans from foreign nations, making him much less powerful . </P> <P> In recent years as a result of devolution, funding for devolved issues to the Scottish Parliament as well as the Welsh and Northern Irish assemblies has been determined through the Barnett Formula . This formula determines the overall budget of the devolved parliaments for devolved issues proportionally relative to spending on those issues in England . As a result, while responsibility for funding of devolved matters rests with the devolved bodies themselves, they in effect must enact policies of a broadly similar cost to those decided by the UK parliament for England and maintain that broad proportionality in order to ensure the long term financial viability of such policies . </P> <P> In the federal government of the United States, the power of the purse is vested in the Congress as laid down in the Constitution of the United States, Article I, Section 9, Clause 7 (the Appropriations Clause) and Article I, Section 8, Clause 1 (the Taxing and Spending Clause). </P> <P> The power of the purse plays a critical role in the relationship of the United States Congress and the President of the United States, and has been the main historic tool by which Congress has limited executive power . One of the most prominent examples is the Foreign Assistance Act of 1974, which eliminated all military funding for the government of South Vietnam and thereby ended the Vietnam War . Other recent examples include limitations on military funding placed on Ronald Reagan by Congress, which led to the withdrawal of United States Marines from Lebanon . </P>

Who has the power to appropriate funds for social programs