Saudi Arabia's King Salman will chair an emergency virtual summit of G20 leaders on Thursday to discuss a global response to the coronavirus pandemic.
World leaders, including Russian President Vladimir Putin, will take part in the talks, which the Kremlin said would take place by video conference.
"King Salman will chair the meeting to advance a co-ordinated global response to the Covid-19 pandemic and its human and economic implications," Riyadh said early on Wednesday.
Saudi Arabia, which holds the G20 presidency, last week called for the "virtual summit" after criticism that the group had been slow to address the crisis.
The G20 members will be joined by leaders from other affected countries such as Spain, Jordan, Singapore and Switzerland.
Leaders from international organisations such as the United Nations, World Bank World Health Organisation and World Trade Organisation will also take part.
Following the announcement, King Salman tweeted on Wednesday: "As the world confronts the COVID-19 pandemic and the challenges to healthcare systems and the global economy, we convene this extraordinary G20 summit to unite efforts towards a global response. May God spare humanity from all harm."
Regional organisations will be represented by Vietnam, the chair of the Association of South-East Asian Nations; South Africa, chair of the African Union; the UAE, chair of the GCC; and Rwanda, chair of the New Partnership for Africa's Development.
China and France on Tuesday supported the idea of the summit as the global death toll from the coronavirus rose to about 16,000 and more than 1.7 billion people were confined to their homes.
Fears are growing that the world economy will be pushed into a recession.
On Monday, Riyadh hosted a video conference with G20 finance ministers and central bank governors to discuss the effects of the Covid-19 pandemic on the global economy.
Mohammed Al Jadaan, Saudi Finance Minister and host of the summit, stressed the need for the G20 to enhance its co-operation in addressing the pandemic.
IMF Managing Director Kristalina Georgieva has welcomed the fiscal and monetary steps taken by some countries, but said more would be needed, especially in the fiscal arena. Surveys show the pandemic is battering the global economy.
Agathe Demarais, global forecasting director at the Economist Intelligence Unit, said given monetary policy constraints, the G20 countries' only option to support growth might be fiscal stimulus, but that could raise the risk of a debt crisis, with "devastating effect on global growth."
"This is something that G20 leaders will have in mind if they go for stimulus packages," Ms Demarais added.
UAE Minister of State and UAE Sherpa to the G20, Ahmed Ali Al Sayegh, virtually attended a pre-meeting on Wednesday to prepare for the leaders' conference on Covid-19.
The meeting addressed efforts by G-20 countries to curb the spread of COVID-19 and mitigate its impact on public health, economic growth, international trade, and international cooperation.
Mr Al Sayegh highlighted the UAE’s commitment to highlighting the serious risks posed to developing and least developed countries during the pandemic, and urged the G-20 to ramp up efforts to support those countries with weaker health systems.
“The need to strengthen multilateral co=operation in efforts to curb the spread of Covid-19 has become increasingly evident as states confront unprecedented challenges to the wellbeing of their peoples and communities,” Mr Al Sayegh said.
“The G-20 platform provides an opportunity for all concerned states to join forces in mitigating the global impact of the coronavirus outbreak and implement strategic, co-ordinated action in pursuit of long-term economic recovery,” he added.
The Saudi presidency is set host world leaders for a summit in Riyadh on November 21 and 22.