Argentina’s Senate on Thursday night comfortably passed a bill to nationalise the country’s private pension funds in the final congressional hurdle for the government’s controversial plan.

A month ago, investors and financial markets were shocked by President Cristina Fernández’s announcement that she planned to nationalise the 14-year-old pension system, and saw the move as an ill-concealed asset grab designed to plug a hole in the government’s $21bn debt servicing requirements next year. The government denied this, saying it was simply rescuing a flawed system that had never worked well.