World leaders came together, virtually, on Monday to mark the 75th anniversary of the United Nations, as the coronavirus pandemic and economic disruption challenge the effectiveness and solidarity of the organization that was set up after the horrors of World War II.

Millions of people were forced into lockdown and economies were devastated as COVID-19 began to spread around the globe earlier this year. Now, some countries find themselves facing a second wave and the 193-member UN has struggled to assert itself in the face of the distrustful United States, an assertive China, and a growing rivalry between the two.

On its own website to mark the anniversary, the UN said the event was taking place at a “time of great disruption for the world, compounded by an unprecedented global health crisis with severe economic and social impacts”.

The coronavirus has intensified long-simmering tensions between the US and China. Washington accuses Beijing of a lack of transparency over the outbreak, which began in the Chinese central city of Wuhan late last year.

In an apparent swipe at Washington, China’s President Xi Jinping said on Monday: “No country has the right to dominate global affairs, control the destiny of others, or keep advantages in development all to itself. Even less should one be allowed to do whatever it likes and be the hegemon, bully, or boss of the world. Unilateralism is a dead end.”

Xi’s remarks were not in the video he recorded for the meeting. They were included in a longer statement that the Chinese UN mission said was submitted to the world body.

China has portrayed itself as the chief cheerleader for multilateralism after US President Donald Trump’s disregard for international cooperation led to Washington abandoning global deals on climate and Iran and leaving the UN Human Rights Council and the World Health Organization (WHO).

The United States President Donald Trump was listed as the first speaker among member states on the UN’s agenda for the event. On the contrary, it was US Acting Deputy Representative to the UN, Cherith Norman Chalet, who spoke in the General Assembly hall.

The world body had in many ways proven to be a “successful experiment”, she said, but added that there were “also reasons for concern”.

The UN has long been resistant to meaningful reform, often lacking in transparency, and vulnerable to the agenda of autocratic regimes and dictatorships, she also added.

People are questioning if this was a deliberate snub or an indication of how important the US feels the UN is in its priority list, she said, speaking from outside the UN headquarters in New York City.

Other leaders spoke of the need for countries to work together on issues such as climate change and the pandemic and lamented the rivalries that were undermining the UN and international cooperation.

“Our shared home is in disarray and foundations are crumbling,” Emmanuel Macron, the French President told the assembly.

“Wars of annexation, chemical weapons use, mass detention are all occurring with impunity,” he continued. “Our international system is held hostage by rivalries and being weakened by its inability to prosecute individuals responsible for these abuses.”

But Trump chose the moment of the UN’s anniversary to impose sanctions on Iran for violating a UN arms embargo and demanded enforcement by US allies, despite his decision in 2018 to unilaterally withdraw the US from the six-power agreement. Allies says he has no authority to make such demands.

UN Secretary-General Antonio Guterres said the pandemic had exposed the world’s fragilities and it can only address with unity. We have a surplus of multilateral challenges today and a deficit of multilateral solutions, he said. We must work together to improve world governance.

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