The U.N. General Assembly held a special session Thursday, with Secretary General Antonio Guterres calling for international cooperation to fight the coronavirus pandemic and help poor countries financially and through other means.

"In a global crisis, we must meet the expectations of those we serve with unity, solidarity and coordinated multilateral global action," Guterres said in his opening remarks for the session held in a virtual format.

While welcoming recent progress toward vaccines against the novel coronavirus, the U.N. chief warned of excessive optimism, saying, "A vaccine cannot undo damage that will stretch across years, even decades to come. Extreme poverty is rising; the threat of famine looms."

U.N. Secretary General Antonio Guterres is shown during an online interview on Sept. 9, 2020. (Photo courtesy of the United Nations)(Kyodo)

Guterres pointed out that although the coronavirus pandemic affects the entire world "regardless of nationality, ethnicity or faith," efforts to address the health crisis differ among countries.

"While COVID-19 does not discriminate, our efforts to prevent and contain it do. For that reason, the pandemic has hit the poorest and most vulnerable in our societies hardest," he said.

The U.N. chief also reiterated that COVID-19 vaccines should be "a global public good available to everyone," while noting that a global mechanism to that end "remains underfunded."

British Prime Minister Boris Johnson said Wednesday that his government will start distribution of a COVID-19 vaccine next week following the approval of one developed by U.S. pharmaceutical giant Pfizer Inc. and German partner BioNTech SE.

As the U.S. biotechnology firm Moderna Inc. has also reported successful results of a final-stage clinical trial, speculation is growing that two vaccines may become available to high-risk populations by the end of December in the United States.

On the other hand, there are concerns that developing countries could be left behind in the distribution of COVID-19 vaccines.

Speaking on behalf of the 120 countries of the Non-Aligned Movement, Azerbaijan President Ilham Aliyev said in his pre-recorded message that he hopes vaccines "will be considered as global public goods, ensuring their universal distribution at affordable prices for all."

Guterres closed his remarks by calling on U.N. member states to seize the opportunity "to confront the COVID-19 pandemic with the urgency it demands; to save lives; and to build a better future together."

On the first day of the special session, which runs through Friday, representatives of many developed and developing countries delivered video messages.

On Friday, U.N. officials such as World Health Organization Director General Tedros Ghebreyesus as well as academics are scheduled to hold a series of discussions on the pandemic.