Christine Lagarde, managing director of the International Monetary Fund (IMF), is confident that the Group of 20 will achieve their target of boosting global growth by 2 percentage points in time for the November summit in Brisbane, she told CNBC on Sunday.

"That's the commitment, that's the goal. The fact that the finance ministers have achieved a global commitment of 1.8 [percentage points] of additional growth by the baseline is a strong indication that they will hit the 2 [percentage point] target," she said at the G-20 meeting in Cairns, Australia.