As the number of coronavirus cases kept climbing worldwide Thursday, former president Barack Obama offered some simple advice for mayors and local leaders battling outbreaks in cities across the globe: “Speak the truth.”

“The biggest mistake any [of] us can make in these situations is to misinform,” Obama said during a virtual meeting organized by Bloomberg Philanthropies, “particularly when we’re requiring people to make sacrifices and take actions that might not be their natural inclination.”

Obama’s comments, addressed to local officials and members of response teams from more than 300 cities, come as millions of people worldwide remain confined indoors, their movements largely restricted by governments attempting to stem the spread of a virus that has no vaccine or scientifically proven treatment. With many feeling fearful and anxious while misinformation about the coronavirus continues running rampant on social media, Obama emphasized the power of truth.

“Speak it clearly. Speak it with compassion,” he said, according to a news release from the foundation. “Speak it with empathy for what folks are going through.”

Obama did not explicitly mention President Trump and directed his remarks to the mayors in attendance. But the former president’s words on Thursday coincided with Trump contradicting experts, who say the need for widespread testing is critical before the country can begin reopening.

Obama was joined Thursday by former New York mayor Mike Bloomberg and several public health experts as part of a series of virtual meetings intended to help mayors tackle challenges associated with the coronavirus, the release said. Previous meetings have featured other former presidents, including George W. Bush and Bill Clinton.

Aside from encouraging fact-based messaging, Obama urged the mayors to “look out for the vulnerable” within their communities, citing reports of disparities in how people are being affected by the virus. Obama also suggested that the local leaders create reliable teams of experts to help bolster their responses.

“The more smart people you have around you, and the less embarrassed you are to ask questions, the better your response is going to be,” he said.

But out of all the comments Obama made during Thursday’s meeting, his call for leaders to avoid misinforming the public appeared to strike a chord.

Since the early days of the pandemic, misinformation about covid-19 has spread almost as quickly as the virus itself, The Washington Post’s Kim Bellware reported in February.

A running list of coronavirus-related hoaxes compiled by BuzzFeed News includes a string of false reports.

“No, the Pope does not have coronavirus.”

“No, Bill Gates did not finance a lab that created COVID-19.”

“No, air purifiers are not an effective way to protect yourself.”

But while fact checkers have worked furiously to debunk such claims, many of them still exist unchecked on popular social media platforms, according to an Oxford University study released on Tuesday.

After examining 225 pieces of information rated false or misleading, the researchers found that nearly 60 percent of the content remained on Twitter without a warning label, The Post’s Craig Timberg reported. According to the study, politicians, celebrities and other public figures are among the “most powerful spreaders of misinformation,” Timberg wrote. The study cited Trump as having made “a number of false statements” on the pandemic in public, including on cable news and Twitter.

Meanwhile, Obama, who boasts a Twitter following of more than 115 million people, is actively fighting coronavirus misinformation online.

In recent months, the former president has started posting to social media more regularly as part of an effort to spread factual information about the coronavirus along with stories about front-line workers and acts of human kindness during the pandemic, The Post’s David Nakamura reported. On Wednesday, for example, Obama weighed in on the debate over maintaining social distancing and reopening the country, tweeting that “in order to shift off current policies, the key will be a robust system of testing and monitoring — something we have yet to put in place nationwide.”

“He’ll continue to lend his voice throughout the pandemic and to remind Americans that we’ll get through this like we’ve done throughout our history: together, looking out for one another,” said Katie Hill, a spokeswoman for Obama.