The number of new coronavirus infections in India has officially surpassed 20 million with 357, 229 new cases reported in the latest 24-hour period.
The health ministry also reported another 3,449 deaths for the same period.
India is now the second nation in the world, after the United States, to pass the grim milestone with health ministry data showing 222,408 deaths since the pandemic began.
The government says infection rates are coming down, after the country set yet another daily global record for COVID-19 cases on Saturday, with 401,993 new infections.
But experts believe the true figure for COVID-19 cases and fatalities is higher.
A recent surge of new infections - faster than anywhere else in the world - has left the healthcare system in the world's second-largest country by population on the brink of collapse.
Dire oxygen shortages are being experienced in India as many hospitals run out, leaving families desperately trying to source some privately to help their loved ones stay alive.
Critics have accused the government of mixed messaging, saying premature declarations of victory during the ongoing pandemic have encouraged people to relax when they should have continued to social distance, wear masks and avoid large crowds.
At least 11 states and regions have ordered curbs on movement to stem infections, but prime minister Narendra Modi's government is reluctant to announce a national lockdown, concerned about the economic impact.
It has also allowed massive crowds to gather for Hindu religious festivals and political rallies before state elections.
The UK has this week announced it was sending an extra 1,000 ventilators to India.
"It's a terrifying crisis," said Dr Punyabrata Goon, of the West Bengal Doctors' Forum.
"It's a day-to-day fight," said B.H. Narayan Rao, a district official in the southern town of Chamarajanagar in Karnataka.
"Every time we have to struggle to get our quota of our oxygen cylinders."
Exams have been postponed for trainee doctors and nurses, freeing them up to join in the fight, while volunteer groups in the capital New Delhi have been providing oxygen to patients in makeshift tents outside a temple.
Gurpreet Singh Rummy, who runs the service, told Reuters: "No one should die because of a lack of oxygen. It's a small thing otherwise, but nowadays, it is the one thing everyone needs."