Hugo Chávez, Venezuela's radical president, led his country into Mercosur yesterday, vowing to inject a strong dose of politics into the languishing South American customs union.

"We have to politicise Mercosur," he said in Montevideo, Uruguay, at a meeting of the group's leaders convened to mark Venezuela's formal entry into the trade bloc. "We cannot allow this to be purely an economic project, one for the elites and for the transnational companies."