"The EU disapproves of the fact that the U.S. decision to impose a travel ban was taken unilaterally and without consultation," the heads of the European Union said Thursday, expressing their displeasure with President Trump's plan to block visitors from 26 European countries from entering the U.S.

"The Coronavirus is a global crisis and requires cooperation," the EU leaders said.

European Council President Charles Michel and European Commission Ursula von der Leyen spoke out the morning after Trump abruptly announced his 30-day ban – rattling an already-shaken travel industry and creating new uncertainty among travelers in both the U.S. and Europe. The United Kingdom is exempt from the ban.

Complicating matters further, Trump left many people scrambling to learn the extent of the ban, which takes effect at midnight Friday. The White House later said the ban applies only to foreign nationals who have been in Europe's open-border Schengen Area.

Trump referred to "exemptions for Americans who have undergone appropriate screenings." Explaining that idea, the White House said U.S. citizens "will be directed to a limited number of airports where screening can take place."

The president's speech set off chaos at airports in Europe and created doubt for Americans who were bound to depart the U.S. — many of whom faced worries that they might not be able to return home, either under the travel ban or a new policy that might be enacted while they're abroad.

The U.S. move came hours after the World Health Organization classified COVID-19 as a global pandemic.

Confusion about Trump's plan was reflected in tweets from two journalists who were on opposite sides of the Atlantic Ocean when he announced the ban.

"Sitting at Atlanta airport after abandoning my flight to France late last night," tweeted reporter Jennifer Berry Hawes of Charleston, S.C.'sThe Post and Courier.

After being blindsided by news of the travel ban, Hawes and a colleague had only an hour to decide whether to fly to Europe as planned. The White House guidance on U.S. exemptions came out nearly two hours after Trump began his speech. Hawes and her coworker opted to stay put rather than risk being stranded in Europe.

The scene was even more frantic at European airports.

"Bedlam at U.S.-bound airlines at [Charles De Gaulle airport] in Paris early this a.m., as Americans pay as much as $20,000 for last-minute flights," reporter Mike McIntire of The New York Times said via Twitter.

McIntire added that he did not pay that large sum — but he said he got an urgent call from a relative in the U.S. after Trump announced the ban, and bought an expensive ticket online as a result.

Trump also said the ban will proscribe "trade and cargo" from Europe, causing more confusion. The White House later clarified that the immigration law invoked by the president's ban "only applies to the movement of human beings, not goods or cargo."

In his address to the nation, the president said:

"To keep new cases from entering our shores, we will be suspending all travel from Europe to the United States for the next 30 days.  The new rules will go into effect Friday at midnight.  These restrictions will be adjusted subject to conditions on the ground."There will be exemptions for Americans who have undergone appropriate screenings, and these prohibitions will not only apply to the tremendous amount of trade and cargo, but various other things as we get approval.  Anything coming from Europe to the United States is what we are discussing."  

Vice President Mike Pence, who is leading the Trump administration's COVID-19 effort, defended Trump's handling of the primetime address, saying "I don't think there was confusion" created by the president's remarks.

In an appearance on CNN Thursday morning, Pence also mentioned that Americans flying home from Europe "will be funneled through 13 different airports" where they will be screened and then asked to self-quarantine. Pence did not name those airports.

The confusion played out as a broader debate continues over the ability of travel bans to contain deadly diseases and protect vulnerable populations from an outbreak.

The morning after Trump spoke, Lawrence Gostin, a public health law expert at Georgetown University, called the president's travel ban "incoherent" and said it would have no impact on the coronavirus outbreak in the U.S. Gostin added that the policy goes against recommendations from the WHO and other international agencies.

"Travel from highly functioning health systems like Switzerland [are] banned, but not weak systems like Russia or Africa," Gostin said. "People are no safer in U.S. than many places banned."

Trump's new policy follows weeks of criticisms of his administration's approach to the coronavirus – particularly its inability to get plentiful supplies of reliable testing kits into the hands of health professionals around the country. In the absence of enough testing, experts say, the U.S. has been unable to monitor or contain the virus.

In his speech, Trump also sought to blame the EU's member countries for failing to contain the virus, saying "a large number of new clusters in the United States were seeded by travelers from Europe."

Before Trump's announcement, his administration had barred visitors from entering the U.S. if they had been in China or Iran in the past 14 days. Those policies, which took effect in February, don't apply to U.S. citizens or people who live in the U.S.

Roughly 105 countries currently have some type of travel restrictions in place because of the coronavirus, according to the IATA international travel site, which tracks such policies. Most of those limits are aimed at reducing ties to hotspots in China and Italy. And while some countries block passengers from France, Germany and Spain – all of which now have more than 2,000 coronavirus patients — the U.S. seems to be the first to prohibit visitors from virtually all of Europe.

"The president of the United States of America has announced an entry ban for most European countries," Royal Dutch Airlines (KLM) says on its web page dedicated to the COVID-19 outbreak. Reflecting the uncertainty over Trump's policy, the airlines adds, "The impact of this measure is still unclear but is being investigated as we speak."

For now, the airline is one of many that are telling would-be passengers to be sure their contact information is up to date, so they can receive news of any changes.

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