Participants of the Group of 20 virtual summit vowed Sunday to spare no effort in making a COVID-19 vaccine widely available to all populations.

Regarding vaccines, tests, and treatment for COVID-19, the disease caused by the coronavirus, "We will spare no effort to ensure their affordable and equitable access for all people," the final communique from the group Sunday said.

U.S. President Donald Trump, who has not made many public appearances since losing the presidential election earlier this month, was scheduled to participate in the meeting Sunday, as he did Saturday.

Saudi Arabia's King Salman opened the summit Saturday by calling on member countries to reassure the world of affordable and equitable access to vaccines.

"We will spare no effort to ensure their affordable and equitable access for all people, consistent with members' commitments to incentivize innovation," the leaders said in a draft G-20 communique seen by Reuters. "We recognize the role of extensive immunization as a global public good."

The pandemic and the crisis of economic recession dominated the first day of the two-day virtual summit of the top 20 industrial and emerging-market countries.

"We have a duty to rise to the challenge together during this summit and give a strong message of hope and reassurance," Salman said as he opened the summit.

The king's comments were made as global coronavirus cases approached 58 million and worldwide COVID-19 deaths neared 1.4 million, according to Johns Hopkins University.

The G-20 leaders are concerned that the pandemic will further widen the divide between rich and poor. To combat that, the European Union urged contributions totaling $4.5 billion to Access to COVID-19 Tools Accelerator, a global project to speed the development and distribution of vaccines, tests and treatment, according to the World Health Organization.

Germany's Chancellor Angela Merkel pledged nearly $593 million. Russia's President Vladimir Putin offered Russia's Sputnik V vaccine, and China offered to cooperate on vaccines.

On Saturday, Trump tweeted about unfounded voter fraud in the November 3 U.S. presidential election during Salman's remarks before leaving to play golf at his club in nearby northern Virginia.

White House press secretary Kayleigh McEnany said he spoke of the need to work together to restore economic growth, but she did not mention a U.S. pledge to support the global distribution of a vaccine in a summary released late Saturday.

After Trump left the virtual meeting, U.S. Treasury Secretary Steve Mnuchin, who also attended, said in a Treasury Department statement that the 7-month-old Debt Service Suspension Initiative "is a key achievement of the G-20 in response to the pandemic." The initiative aims to help the world's poorest countries grapple with the consequences of the pandemic until the middle of next year.

Treasury's statement also said the G-20's Common Framework would help the poorest countries address pandemic-induced debt problems "by coordinating sovereign debt resolution if needed."

The summit is being held mostly online for the first time this year because of the COVID-19 pandemic.

G-20 member countries include Argentina, Australia, Brazil, Britain, Canada, China, France, Germany, India, Indonesia, Italy, Japan, Mexico, Russia, Saudi Arabia, South Africa, South Korea, Turkey, the United States and the European Union.

They represent, according to the group's website "around 80% of the world's economic output, two-thirds of global population and three-quarters of international trade."