In the late 1840s, the Argentine Confederation attempted to regulate traffic on the Paraná and Uruguay rivers, which impacted upon Anglo-French trade with the landlocked Paraguay. As a result, Britain and France took military action in the blockade of the Río de la Plata. Although militarily successful, the victories against Argentine forces proved somewhat pyrrhic and both withdrew their forces and made treaties with Argentina. The peace treaty with the British is referred to as the ; or the Arana–Southern Treaty.