A South African flag-coloured King Protea flower - symbolising hope and regeneration - is the chosen logo for this year's G20 Leaders' Summit, taking place on African soil for the first time.
"Now is the time for leadership and vision," the UN Secretary-General António Guterres told journalists in Johannesburg on Friday, a day ahead of the official opening.
The G20 bloc is made up of the world's largest economies, although the United States has announced it will not officially participate.
This year's summit highlights the need for climate adaption and sustainable financing, under the theme "Solidarity, Equality and Sustainability."
The UN chief is attending the summit to push for economic and climate action, as well as an end to spiralling conflicts around the world.
'Woefully under-represented'
Developing countries, in particular in Africa, are suffering from a shrinking fiscal space, crushing debt burdens and a global financial architecture that is failing them, Mr. Guterres said.
He lamented that after decades of colonial rule, the continent remains "woefully under-represented" in global institutions.
"The G20 can help repair this historic injustice and drive reforms that give developing countries - and Africa in particular - a real voice in shaping global policies, and make global economic governance more inclusive, representative, equitable and effective in the years ahead," he said.
Economic action
Mr. Guterres called on the G20 to live up to commitments made in June at the Financing for Development Conference in Sevilla , where countries promised to unlock more finance to drive sustainable growth.
That would entail tripling the lending power of multilateral development banks, reducing borrowing costs and enabling developing countries to mobilise domestic resources.
Climate action
Countries have failed to keep temperatures to the 1.5 degrees Celcius temperature rise limit, Mr. Guterres cautioned.
"Avoiding more climate chaos means bridging the adaptation gap - urgently" and that requires a scale up of financing, namely, the doubling of adaptation financing to at least $40 billion this year.
He added that while 90 per cent of new power capacity is coming from renewables, while global investment in clean energy reached $2 trillion last year, only a negligeable proportion went to Africa.
"Africa should be at the heart of this clean energy revolution," he pressed.
Action for peace
Listing some of the most devastating conflicts around the world including in Sudan, the Democratic Republic of Congo, Ukraine and Gaza, Mr. Guterres called for G20 members to use their influence to end the fighting.
"Everywhere - from Haiti to Yemen to Myanmar and beyond - we must choose peace anchored in international law," he concluded.
