(CNN) President Donald Trump told governors they can reopen their states soon if they want but health officials across the country are still battling numerous coronavirus outbreaks.

"Our national shutdown is not a sustainable long-term solution," Trump told reporters.

Trump unveiled new guidelines on Thursday to help states loosen social distancing restrictions and restart the economy. The guidelines, which won't be mandatory, suggest a phased approach that will still keep schools closed and allow some restaurants and gyms to operate under social distancing protocols. Each governor will ultimately decide on how and when to open.

"We are not opening all at once, but one careful step at a time," Trump said. "And some states will be able to open up sooner than others. Some states are not in the kind of trouble that others are in."

While the number of new cases is dropping in some states, health officials have identified new outbreaks. In New Hampshire, clusters were identified at three long-term care facilities, according to Lori Shibinette, health commissioner with the New Hampshire Department of Health and Human Services.

Meanwhile, more than half of the 143 new cases of Covid-19 in South Dakota were linked to the Smithfield Foods plant, one of the country's largest pork processing facilities, a spokesman with the state's health department said.

An influential model previously cited by the White House shows that number of new cases has dropped on a national level while "places like New York seem to be stuck at the peak for longer than we originally expected."

Dr. Christopher Murray, director of the Institute for Health Metrics and Evaluation at the University of Washington, told CNN's Anderson Cooper during CNN's coronavirus town hall those hot spots are seeing longer peaks than what Spain and Italy experienced. He noted that Southern states will not be hit as hard as initially estimated.

More than 670,000 people have tested positive in the US with at least 33,101 deaths linked to the virus, according to a tally by Johns Hopkins University . About 4,811 deaths were reported Wednesday alone.

It's unclear whether the latest death toll includes probable cases. Federal health officials have said they'll start including probable cases , which meet clinical criteria for symptoms and evidence of Covid-19 -- but with no lab test confirming the disease.

Governors extended stay-at-home orders and formed pacts

Several governors extended stay-at-home orders to fight the coronavirus and new partnerships had emerged among them before Trump told them they will call their "own shots."

Seven states -- Michigan, Ohio, Wisconsin, Minnesota, Illinois, Indiana and Kentucky -- will work together to reopen the Midwest regional economy, Michigan Gov. Gretchen Whitmer announced.

"We will make decisions based on facts, science, and recommendations from experts in health care, business, labor, and education," Whitmer said in a statement.

New York and six other Northeast states extended stay-at-home orders through at least May 15. Los Angeles Mayor Eric Garcetti has said his city will likely not permit public sporting events and concerts until next year.

Louisiana Gov. John Bel Edwards announced the creation of the "Resilient Louisiana" task force, which will work toward the reopening of the state's economy.

Edwards says experts will make recommendations on how to reopen businesses in a way that adequately protects public health.

More testing is needed before reopening, officials say

Before social distancing mandates are relaxed, authorities and experts say that increased coronavirus testing will have to be conducted nationwide to track how much the virus has penetrated communities and enable officials to separate those who are infected.

Following Trump's call with the governors, North Carolina Gov. Roy Cooper emphasized the need for testing and personal protective equipment, noting the federal government should step in.

"We will continue working with our federal and local partners to beat this virus, protect people's health and recover our economy," Cooper said in a statement.

Washington Gov. Jay Inslee called rapid testing the key to determining when emergency restrictions can be lifted. "We need to build the equivalent of a fire brigade," he said.

Unemployment claims continue rising

Another 5.2 million Americans filed for their first week of unemployment benefits in the period ending April 11, according to new figures by the US Department of Labor.

In total, 22 million people have filed first-time claims since mid-March as the pandemic forces businesses to close and lay off workers.

The Small Business Administration said it had run out money for the Paycheck Protection Program and was unable to accept new applications.

With the $349 billion emergency small business lending program out of funds, Treasury Secretary Steven Mnuchin and Democrats will reconvene Thursday on a package to increase funding immediately.

Former Vice President Joe Biden called choosing between reopening the economy and ending the pandemic a "false choice."

"Look, I think it's a false choice to say you have to choose between the economy and our health. If you don't fix the health side of it, the economy is never going to get right," he said during CNN's coronavirus townhall on Thursday.

Protesters rally against restrictions in two states

Medical experts have emphasized that the key to fewer coronavirus cases is for people to practice social distancing. As a result, all but seven states are under stay-at-home orders from their governors.

But in at least two states, protesters rallied against the social distancing mandates, calling them a violation of individual freedoms.

Protesters rallied outside the North Carolina State Legislature in Raleigh.

In Lansing, Michigan, vehicles jammed several streets around the Capitol in a protest organized by conservative groups against Democratic Gov. Gretchen Whitmer.

"It's time for our state to be opened up. We're tired of not being able to buy the things that we need," Brenda Essman of Kalamazoo told CNN affiliate WLNS. "We need to open our businesses."

And in Raleigh, North Carolina, demonstrators gathered outside the state legislative building Tuesday to protest the state's stay-at-home order, CNN affiliate WRAL reported. Police officers told them they were defying social distancing rules by standing too close together, and asked them to disperse. Most left.

Michigan is one of the hardest-hit states with nearly 2,000 deaths reported while North Carolina has had 135.

Companies report changes in testing

Some commercial lab companies say they've seen some recent decline in demand for coronavirus tests following weeks of increases.

Quest Diagnostics said demand declined in recent days, allowing the company to wipe out the remnants of its coronavirus test backlog. Its average turnaround time is now less than two days.

Another company, Eurofins USA, said its labs have excess testing capacity, in part because many hospitals are now testing in-house. A company spokesperson said another contributing factor is some of its labs have been denied entry into some insurance plan networks.