The annual parade of presidents, prime ministers, princes and potentates starts off on Tuesday in New York City when they meet in person and virtually at the United Nations General Assembly to grapple with global problems, promote their own agendas and engage in diplomacy. Afghanistsan, climate change, with the UN climate change conference in Glasgow scheduled for November, and the COVID-19 pandemic, especially vaccine equity, are expected to be among the top items on the agenda for the meetings billed as the High-Level Week that will be held under the leadership of General Assembly President Abdulla Shahid, the Foreign Minister of Maldives.

These topics are expected to dominate Secretary-General Antonio Guterres's speech at the opening session, according to a UN source familiar with his thinking. He will sound a “five-alarm” warning on the dangerously deteriorating global situation in these and other areas, the source said.

The source said that Guterres is also expected warn about the risks from tensions between the US and China.

By tradition, Brazil is scheduled to be first national speaker at the session. Brazil's President Jair Bolsonaro is to be in person at the Assembly on Tuesday followed by US President Joe Biden.

Prime Minister Narendra Modi is set to address the Assembly in person on Saturday at the start of the day's session at 9 am New York time (6:30 pm Indian Standard Time) after his visit to Washington for the Quad summit.

Ahead of his speech, which is expected to highlight India's contribution of vaccines in the global war on the pandemic, New Delhi has announced that it will resume exports vaccines that many countries desperately need.

Global security and terrorism have been the mainstays of his UN speeches and the topics take on urgency after the Taliban takeover of Afghanistan.

External Affairs Minister S. Jaishankar arrived in New York on Monday for diplomacy on the sidelines of the Assembly.

He will represent India at several of the meetings held alongside the Assembly sessions and also hold bilateral talks with many leaders starting with British Foreign Secretary Elizabeth Truss who took over the job last week.

The side events dealing with specific topics started off on Monday with an informal roundtable of some heads of state and government on climate change that was convened by Britain's Prime Minister Boris Johnson and Guterres.

A virtual COVID-19 summit convened by Biden on Wednesday will be one of the major events on the sidelines of the Assembly and his Spokesperson Jen Psaki said it will be an effort for “expanding and enhancing our shared efforts to defeat” the pandemic.

Amid fears that the UN event could become a Covid super-spreader, the participation has been pared down and 54 of the speakers will address the Assembly virtually.

The others will come with smaller delegations.

China and Russia are listed among those sending in pre-recorded statements.

Russia's virtual representation has been downgraded with only Foreign Minister Sergey Lavrov scheduled to speak on Saturday.

France's President Emmanuel Macron, whose country is engaged in a diplomatic tiff with the US, cancelled his virtual speech scheduled for Tuesday. Foreign Minister Jean-Yves LeDrian is expected to speak later in the week.

The two countries are at odds over the breach of Australia's contract to buy submarines after the US offered Canberra nuclear-powered submarines.

Beijing was originally scheduled to be represented by a deputy prime minister on Saturday afternoon, but on Monday there was a late switch and President Xi Jinping is now scheduled to speak virtually on Monday at the end of the morning session.

According to sources at the UN, Xi asked for the change so he could respond to any possible critical statements by Biden and highlight his country's contributions to fighting climate change and the Covid pandemic and avoid being overshadowed by Biden.

Although Pakistan Prime Minister Imran Khan was marked on the roster as speaking in person on Thursday, sources at the UN said that he will instead send a pre-recorded statement.

Foreign Minister Shah Mahmood Qureshi, however, will arrive here Monday evening to promote his country's causes in person, especially after its ally Taliban overran Afghanistan.

Khan's standard outbursts against India and the BJP that has consumed the bulk of his previous addresses can be expected to be repeated again.

As in previous years, a junior diplomat from India's UN mission may respond to him.

Although the Taliban has taken over Afghanistan and announced its government, Ghulam Isaczi, who was appointed Permanent Representative by the democratically elected President Ashraf Ghani, continues to represent his country at the UN.

He is to be the last speaker of the High Level Week and is expected to attack the Taliban's usurpation of power and its regressive policies while asking countries not to recognise the regime.

Myanmar's Permanent Representative Kyaw Moe Tun, who was appointed by the democratically elected government that was overthrown by the military will also speak for his country, also on Monday.

They will continue to represent their countries until the Assembly's Credentials Committee meets to decide who should be recognised as their envoys.

The issue of Afghanistan's representation may scuttle the foreign minister's meeting of the South Asian Association for Regional Cooperation, which is usually held on the sidelines of the Assembly session but has not been scheduled. Afghanistan's Foreign Minister Amir Khan Muttaqi will not be coming to UN.

In his speech on Tuesday, Biden will focus on fighting Covid and climate change, the State Department's senior official for international organisations, Erica Bark-Ruggles, said.

“As defeating COVID-19 is the highest priority for the United States, it is also a top priority of ours during the UN General Assembly,” she said.

He will ask all countries to do more to deal with the Covid pandemic and with the climate crisis, she said.

She added that Biden will also voice support for “the rules-based international system” -- a term that refers to China's aggressive expansionist policies.