New Jersey Gov. Phil Murphy announced Monday that the state’s requirement to wear face masks in schools will end on March 7.

"Balancing public health with getting back to some semblance of normalcy is not easy. But we can responsibly take this step due to declining COVID numbers and growth in vaccinations," Murphy tweeted.

Murphy, a Democrat, has imposed some of the strictest pandemic-related mandates in the country. New Jersey, an early hot spot for COVID-19 cases, has lost more than 31,000 residents to the virus.

This move follows a decision last month by Pennsylvania Gov. Tom Wolf, also a Democrat, to rescind his state's mask mandate for schools.

Meanwhile, the Democratic governors of New York and Connecticut have said that they are reevaluating school mask mandates set to expire later this month.

-ABC News' Aaron Katersky

After months of rising cases due to the omicron surge, every state in the U.S. is now reporting declining or stable new case rates, according to federal data.

Less than one month ago, the U.S. was averaging more than 800,000 new cases per day. Now that average has plummeted to just over 313,000 new cases per day -- a 61% drop since the nation's peak in mid-January and a 56% drop in the last two weeks. 

Even so, the U.S. still reported nearly 2.2 million new COVID-19 cases last week; the nation's daily case average remains higher than during any other wave of the pandemic.

Hospitalizations are also falling. About 14,000 Americans are being admitted to the hospital with COVID-19 each day -- down by more than 23% in the last week, according to federal data.

Deaths, however, remain very high, with 16,800 Americans dying from COVID-19 over the last week. Deaths are a lagging indicator and usually take a few weeks to dip after the country sees a decline in cases and hospitalizations.

-ABC News' Arielle Mitropoulos

Delaware will lift its universal mask mandate on Friday morning after an improvement in cases and hospitalizations, Gov. John Carney said.

"We’re in a much better place than we were several weeks ago," Carney said in a statement Monday. “I want to be clear about this point - COVID is still circulating in our communities. And the virus still poses a risk of serious illness, particularly among those who are not up to date on their vaccinations. But we have the tools to keep ourselves and each other safe."

The mask requirement for Delaware schools was extended and is now set to expire on March 31.

Canada's capital declared a state of emergency on Sunday because of trucker-led protests against COVID-19 vaccine mandates and other pandemic-related restrictions.

The move by Ottawa Mayor Jim Watson "reflects the serious danger and threat to the safety and security of residents posed by the ongoing demonstrations and highlights the need for support from other jurisdictions and levels of government," according to a statement from the city.

"It also provides greater flexibility within the municipal administration to enable the City of Ottawa to manage business continuity for essential services for its residents and enables a more flexible procurement process, which could help purchase equipment required by frontline workers and first responders," the city said.

Seven people were arrested in Ottawa on Sunday due to enforcement measures around the demonstration, according to a press release from the Ottawa Police Service.

"There are over 60 criminal investigations so far related to the demonstration," police said. "They are primarily for mischief, thefts, hate crimes and property damage."

Sunday marked the 10th straight day of the so-called "freedom convoy" protests, which began with truckers critical of a new rule that they must be vaccinated against COVID-19 to cross the United States-Canada border. The demonstrations have since grown into broader challenges to pandemic-related public health measures and opposition to Canadian Prime Minister Justin Trudeau.

Thousands of protesters have occupied the streets of Ottawa and other cities across Canada in support of the movement, paralyzing the capital's city center with traffic jams, nonstop noise and complaints of harassment. Protesters have said they won't leave until all COVID-19 vaccine mandates and restrictions are lifted nationwide. They are also calling for the removal of Trudeau's government, even though most of the public health measures were put in place by provincial governments.

Pfizer said it has postponed its application to the FDA to expand the use of its COVID-19 vaccine for kids under 5.

Pfizer instead will continue with its study on the three-dose vaccine and seek authorization when that data is available.

"We believe additional information regarding the ongoing evaluation of a third dose should be considered as part of our decision-making for potential authorization," Pfizer said.

Dr. Peter Marks, the FDA’s vaccine chief, told reporters Friday, “We realized now, in data that came in very rapidly because of the large number of cases of omicron, that at this time, it makes sense for us to wait until we have the data from the evaluation of a third dose before taking action."

Marks acknowledged that the change was “late breaking” -- the FDA’s committee of independent advisers was scheduled to review and vote on authorizing the vaccine next week -- but said the job of the FDA was to “adjust” to new data amid an unpredictable virus.

“The data that we saw made us realize that we needed to see data from a third dose as in the ongoing trial in order to make the term determination that we could proceed with doing an authorization,” Marks said.

Pfizer has predicted it will be able to submit data on the third dose in early April.

-ABC News' Eric M. Strauss, Cheyenne Haslett