The United States is "not in a good place" as some areas report upticks in COVID-19 infections and hospitalizations, according to Dr. Anthony Fauci, the nation's leading infectious diseases expert.

"As we get into the fall and the winter, you really want the level of community spread to be as low as you possibility get it," Fauci, the director of the National Institute of Allergy and Infectious Diseases and a key member of the White House coronavirus task force, told ABC News in an interview Monday on "Good Morning America."

"There's certainly parts of the country that are doing well," he added. "But ... there are states that are starting to show uptick in cases and even some increases in hospitalizations in some states. And, I hope not but, we very well might start seeing increases in deaths."

"You don't want to be in a position like that as the weather starts getting cold," he warned. "So we really need to intensify the public health measures that we talk about all the time."

When asked about Florida's recent decision to reopen bars and restaurants at full capacity and suspend fines for not wearing masks, Fauci called it "very concerning."

"That is something that we really need to be careful about, because when you're dealing with community spread and you have the kind of congregate setting where people get together particularly without masks, you're really asking for trouble," he said. "Now's the time actually to double down a bit."

That doesn't mean another shutdown, he noted.

"We're not talking about shutting anything down. We're talking about common sense type of public health measures that we've been talking about all along," he said. "Obviously, if things really explode you'd have to consider that. But we want to do everything we possibly can to avoid an absolute shutdown."

As the global death toll from the coronavirus pandemic edges closer to 1 million, Fauci warned that the situation is "very serious."

"You got to take it very seriously," he said.

There were a 1,125 patients hospitalized due to COVID-19 across Missouri on Sunday, the highest number the U.S. state has reported since the start of the pandemic.

It was the third straight day that Missouri had logged a record number of COVID-19 hospitalizations. There were 1,068 patients on Friday and 1,101 on Saturday, according to data from the Missouri Department of Health and Senior Services.

Overall, Missouri has confirmed 123,406 COVID-19 cases with 2,063 deaths. The state's seven-day positivity rate for COVID-19 tests stands at 11.8%, according to health department.

Bars and restaurants in the French port city of Marseille and nearby Aix-en-Provence were forced to shut their doors on Sunday night for a week, as part of local measures to stem rising COVID-19 infections.

The situation will be reassessed after seven days, and the closures could be extended another week. The affected businesses are allowed to operate delivery and take-out services in the meantime.

"The virus is still circulating, and our battle continues," French Health Minister Olivier Veran wrote on Twitter Sunday. "I understand the anger at the closure of bars [and] restaurants in Marseille, Aix, and the time limits in other cities. But this decision is neither final nor arbitrary: it limits the spread of the virus [and] avoids the saturation of hospitals."

Bars and restaurant owners in Marseille took to the streets Monday to protest the closures. One protester held a sign that read, "Veran killed me."

France is not the only country seeing a resurgence in COVID-19 cases. Other European nations including Spain and the United Kingdom are also grappling with growing outbreaks.

ABC News' Ibtissem Guenfoud contributed to this report.

There were 36,919 new cases of COVID-19 identified in the United States on Sunday, according to a real-time count kept by Johns Hopkins University.

Sunday's tally is well below the country’s record set on July 16, when there were 77,255 new cases in a 24-hour-reporting period.

An additional 266 coronavirus-related fatalities were also recorded Sunday, down from a peak of 2,666 new fatalities reported on April 17.

A total of 7,115,338 people in the United States have been diagnosed with COVID-19 since the pandemic began, and at least 204,758 of them have died, according to Johns Hopkins. The cases include people from all 50 U.S. states, Washington, D.C. and other U.S. territories as well as repatriated citizens.

By May 20, all U.S. states had begun lifting stay-at-home orders and other restrictions put in place to curb the spread of the novel coronavirus. The day-to-day increase in the country's cases then hovered around 20,000 for a couple of weeks before shooting back up and crossing 70,000 for the first time in mid-July. The daily tally of new cases has gradually come down since then but has hovered around 40,000 in recent weeks.

An internal memo from the Federal Emergency Management Agency obtained by ABC News on Friday night shows that the number of new cases recorded in the United States is continuing to increase significantly while the number of new deaths is decreasing substantially in week-over-week comparisons.