Brazil's daily Covid-19 death toll has passed 3,000 for the first time as the virus continues its rapid spread, pushing hospitals close to collapse.
The country has reported 298,676 deaths linked to the virus since the start of the pandemic, with experts saying the situation is virtually out of control.
President Jair Bolsonaro, who has opposed lockdowns and criticised face masks, defended his actions on Tuesday.
Pot-banging protests were held in major cities during his televised address.
The far-right president - who repeatedly played down the virus, raised doubts about vaccines and defended unproven drugs as treatment - said he would make 2021 the year of vaccinations.
"Very soon we'll resume our normal lives," said the president, who has been under heavy criticism at home and abroad. Shortly before his four-minute speech, the health ministry reported that 3,251 people had died with the virus in the previous 24 hours.
Brazil has been struggling with the rollout of its vaccination programme, with 6.64 doses administered per 100 people, according to the Our World in Data tracker. Critics say the Bolsonaro government was slow in negotiating supplies amid a worldwide run, leaving Brazil facing delays in receiving jabs.
The worsening of the Brazilian outbreak is also attributed to the spread of highly contagious variants of the virus. States and cities have announced a number of measures in recent weeks to limit the movement of people in an attempt to slow contagion.
The president has argued that the collateral damage to the economy brought by restrictions would be worse than the effects of the virus itself, a view shared by many of his supporters. But his attempt to stop local authorities from imposing them was blocked by the Supreme Court on Tuesday.
Many hospitals are running out of ICU beds and drugs needed to treat critically ill patients are in short supply. Six states also reported "worrying" levels of medical oxygen supplies, the prosecutor general's office said.
On Tuesday, the leading health institute Fiocruz urged authorities to co-ordinate a national response and close non-essential businesses in all but two states for 14 days. "Partial and isolated measures will only prolong this health crisis," the institute's researchers said.
To date, Brazil has reported more than 12.1 million cases, according to the health ministry.
The director of the Pan American Health Organization, Carissa Etienne, said the virus continued "to surge dangerously across Brazil", urging all Brazilians to adopt preventive measures.
"Unfortunately, the dire situation in Brazil is also affecting neighbouring countries," she added, saying that cases had risen in border regions of Venezuela, Peru and Bolivia.
Also on Tuesday, President Bolsonaro swore in cardiologist Marcelo Queiroga as his fourth health minister since the pandemic began. He replaces Eduardo Pazuello, an active-duty army general who is under investigation at the Supreme Court over alleged negligence.
Analysts say it is not yet clear how much freedom Mr Queiroga will have to implement policies aimed at curbing the virus. Mr Pazuello's two predecessors both left government after clashing with President Bolsonaro's positions on Covid-19.