Sluggish global economic growth was of concern to all at the G20 leaders summit held in Brisbane, Australia, Finance Minister Nhlanhla Nene said on Tuesday.

"Leaders noted that the world economy is not growing fast enough due to the lack of global demand and supply constraints," Nene told reporters in Pretoria.

"They agreed while there might be scope in some countries to still use macro-economic policies to stimulate and support the economy, a bigger boost will have to come from country-specific structural reforms."

He said discussions in Brisbane centred on strategies by all countries that would contribute to the objective of adding a further two percentage points to baseline growth estimates over the next five years.

Nene said there was "robust discussion" regarding calls for the reformation of international financial institutions, particularly the International Monetary Fund (IMF).

"It was agreed that the international financial institutions needed to be reformed to reflect the fact that the emerging markets and developing economies now account for the largest share of global growth," said Nene.

"This shift in the structure of the global economy must be reflected in the governance structures of multilateral institutions such as the IMF and the World Trade Organisation."

President Jacob Zuma led the South African delegation to the summit, which took place on November 15 and 16.

Zuma was accompanied by Nene and International Relations Minister Maite Nkoana-Mashabane.