The head of the International Monetary Fund has apologized to UK Chancellor George Osborne for the agency's modest estimation of Britain's economic growth.

In 2013, the IMF had predicted that the UK economy would only grow by 0.7 percent. "Growth has rebounded more strongly than anticipated in the UK on easier credit conditions and increased confidence," an IMF report had said at the time. "However, the recovery has been unbalanced, with business investment and exports still disappointing." However, Britain's GDP grew by 1.7 percent.

"Do I have to go on my knees?" said IMF chief Christine Lagarde. "We got it wrong. We acknowledged it. Clearly the confidence building that has resulted from the economic policies adopted by the government has surprised many of us.

"We said very clearly that we had underestimated growth for the UK and that our forecasts had been proven wrong by the reality of economic developments," she said, adding: "The mixture between tax and spending cuts is something that we regard as fairly balanced and at the right mix. We don't see a massive increase in tax as recommendable at the moment."

Furthermore, in April this year, the IMF declared that Britain will be the fastest growing Western economy in 2014, and upgraded its forecast for UK growth to 2.9 percent in 2014, up from its previous estimate of 2.4 percent.

Speaking on BBC's Andrew Marr Show, Lagarde also hit back at Labour Party leader Ed Miliband's tax rise plans stating they are "not recommendable."