More than 100 million people around the world have now been infected with Covid-19, according to data compiled by Johns Hopkins University.
The United States remains the worst-hit country, recording more than 25 million cases and 420,000 deaths.
President Joe Biden, who has promised a fierce fight against the pandemic, has set a goal of administering at least 100 million vaccinations in his first 100 days in office.
India and Brazil have the second and third highest case tallies after the US, standing at more than 10.6 million and 8.8 million infections respectively.
It is well understood that the true number of cases is likely to be far higher than what has been reported.
Countries continue to exceed grim milestones, with more than 100,000 people dying in the United Kingdom after contracting coronavirus.
The UK's health department said 100,162 people had died after testing positive for Covid-19, including 1631 new deaths reported on Tuesday. Britain is the fifth country in the world to pass that mark, after the United States, Brazil, India and Mexico.
Indonesia has confirmed more than 1 million coronavirus infections, with hospitals in some hard-hit areas nearing capacity.
Indonesia's health ministry announced new daily infections rose by 13,094, bringing the country's total to 1,012,350 - the most in South-East Asia.
'Every moment counts' - WHO boss
The World Health Organisation (WHO) chief has doubled down on calls for a more equal distribution of Covid-19 vaccines.
Director-General Tedros Adhanom Ghebreyesus says least-developed countries have to "watch and wait" while richer countries power ahead with their immunisation programmes.
"Vaccine nationalism might serve short-term political goals but it's in every nation's own interest to support vaccine equity," Dr Ghebreyesus said.
With Africa struggling to secure sufficient vaccines to start countrywide inoculation programmes for its 1.3 billion people, the international Gavi vaccine alliance meanwhile has said the surplus doses that richer countries had ordered ran into the hundreds of millions.
The WHO chief urged countries around the world not to "squander" the window of opportunity that vaccines gave them to curb the spread of coronavirus, and criticised what he described as a growing divide between richer and poorer countries in the procurement of vaccines.
"The stakes could not be higher. Every moment counts," he said.
The African Union this month secured 270 million shots for the continent to supplement 600m doses from the Covax vaccine distribution scheme co-led by the WHO and Gavi.
Those doses are expected to become available this year but none have arrived yet, while parts of Europe, Asia and the Americas are well into their vaccination programmes.
Britain has ordered 367m doses of seven different vaccines - some already approved and some candidate drugs - for its population of roughly 67m, while the European Union has secured nearly 2.3 billion doses for its 450m people.
Last week the WHO chief warned that the world was on the brink of a "catastrophic moral failure" of equitable delivery of vaccines.
Virus origins remain a 'big, black box'
A relative of a coronavirus victim in China is demanding to meet a visiting World Health Organisation expert team investigating the origins of the virus.
They say they should speak with affected families who allege they are being muffled by the Chinese government.
Zhang Hai's father died of Covid-19 in February 2020. He has been organising relatives of victims to demand accountability from officials.
Zhang says he is worried the WHO might be used to provide cover for alleged Chinese mis-steps in the early days of the outbreak.
WHO says the visit is a scientific mission to investigate the origins of the virus, not an effort to assign blame. The WHO team is expected to begin fieldwork later this week.
Anthony Fauci, the top infectious disease official in the US, told the World Economic Forum that the origins of the virus are still unknown, "a big, black box, which is awful".
Keiji Fukuda, a public health expert at the University of Hong Kong and former WHO official says investigators need access.
"It all comes down to what will the team have access to," he said.
"Will they really be able to ask the questions that they want to ask?"