UNITED NATIONS - United Nations Secretary-General Antonio Guterres on Thursday called on member states to make vaccine solidarity a top priority.

"Our first priority for 2021 is to respond to COVID-19. Vaccines are the first great moral test before us," the UN chief told the UN's 193 member states.

Outlining his priorities for the months ahead, the secretary-general emphasized that vaccines "must be seen as global public goods - people's vaccines - available and affordable to all".

"Vaccines are reaching a handful of countries quickly, while the poorest countries have almost none. Science is succeeding - but solidarity is failing," the top UN official underscored.

"Governments have a responsibility to protect their populations, but COVID-19 cannot be beaten one country at a time," said the secretary-general.

He said that recent studies have found that vaccine hoarding could cost the global economy up to 9.2 trillion US dollars - with almost half of that impact in the wealthiest countries themselves.

Guterres urged countries to step up support to the COVAX Facility, the international coalition working to make these treatments available and affordable to all.

"There is only one victor in a world of vaccine haves and vaccine have-nots: the virus itself," he stressed.

"2020 brought us tragedy and peril. 2021 must be the year to change gear and put the world on track," he said, speaking from the podium in the General Assembly Hall.

"We need to move from death to health; from disaster to reconstruction; from despair to hope; from business as usual, to transformation."

The secretary-general has called for "a global reset" as the world continues to reel from the COVID-19 pandemic, which has claimed more than 2 million lives and some 500 million jobs.

He said the crisis is an opportunity for change, stating that "we can move from an annus horribilis to make this an 'annus possibilitatis' - a year of possibility and hope".

However, the world cannot heal if economies are on life support, the secretary-general continued, underscoring how post-pandemic recovery must be both inclusive and sustainable.

Countries must invest now in sectors such as health, social protection, employment, and education.

The UN chief was concerned about developing nations, which have lost out hugely on remittances and tourism revenue due to the crisis, and he highlighted the need for debt relief and financial support.

"Recovery must also be sustainable - embracing renewable energy, and green and resilient infrastructure," he added. "Otherwise, we will lock in harmful practices for decades to come."

Making peace with nature is another top priority for 2021, which the secretary-general described as "a critical year" for climate and biodiversity.

"I call on every city, company and financial institution to adopt concrete roadmaps with clear intermediary milestones to get to carbon neutrality by 2050. Key sectors such as shipping, aviation, industry and agriculture must do the same," he said.

Guterres challenged countries to phase out coal power over the next two decades, and to end subsidies for fossil fuels, urging them to "shift the tax burden from income to carbon, from taxpayers to polluters".

The UN chief again expressed solidarity with developing nations, particularly small island developing states confronting the existential threat of climate change.

"Their territories could disappear within our lifetimes," he warned. "We must never allow any member state to be forced to fold its flag because of a problem that is within our power to fix."

With extreme poverty and hunger rising, the pandemic has worsened inequalities and injustices. Human rights and basic freedoms are also under threat, as women, girls, minorities and LGBTI people experience chronic discrimination and violence.

In welcoming new momentum in the global fight for racial justice, the secretary-general underlined the UN's commitment to promoting tolerance.

"We must all stand up against the surge of neo-Nazism and white supremacy," he said.

"The United Nations will never veer from its commitment to fight racism and discrimination. There is no place for racism within our organization - and we will continue our work to root it out."