BRUSSELS (AP) — The European Union's top official on Monday called for more coordination and insisted on the need to keep the 27-nation bloc's internal borders open as much as possible as member states implement measures to slow the spread of the novel coronavirus.

After the surge of COVID-19 cases in Europe led the Italian government to put the country on lockdown, other member states have implemented drastic measures and travel restrictions, including partially closing their borders.

"Our measures to contain the Coronavirus outbreak will be effective only if we coordinate on the European level," European Commission president Ursula von der Leyen said. "We have to take exceptional measures to protect the health of our citizens. But let's make sure goods and essential services continue to flow in our internal market. This is the only way to prevent shortages of medical equipment or food."

European Union leaders are set to hold a summit via video-conference Tuesday on efforts to contain the spread of the virus, which has now infected more than 50,000 people across Europe, and claimed more than 2,000 lives.

With Italy reporting the most virus cases and deaths anywhere in the world except China, neighboring countries including Austria and Slovenia have moved to slow traffic. But other EU nations, including Germany, Poland, Slovakia and Cyprus have also introduced restrictions that could damage the bloc's economy and slow down the circulation of medical equipment.

Austria, Hungary, Czech Republic, Poland, Lithuania and Germany plus non-member Switzerland have notified the commission that they have taken immediate steps under the EU's border rule book allowing member states in exceptional circumstances to reintroduce border checks for a limited period. The EU's borders code stipulates that the initial period of 10 days can be renewed for up to two months.

The different approaches in different countries are raising concerns that vital medical equipment may be blocked. The EU is urging its members to put common health screening procedures in place at their borders to limit the spread of the virus, but not to block the transport of important medical equipment.

In a series of guidelines for border management measures, the commission urged member states to facilitate the circulation of workers, to ensure an efficient movement of goods and to impose restrictions only when they are "duly motivated" and science-based.

"Member States should preserve the free circulation of all goods. In particular, they should guarantee the supply chain of essential products such as medicines, medical equipment, essential and perishable food products and livestock," the commission said.

Jon Worth, a visiting lecturer at the College of Europe in Bruges, said he was not surprised that member states decided to restrict the movement of people at their borders given that health care is a matter of national responsibility in the EU.

"But the single market is definitely the EU's responsibility and they have to make sure the chain of supply does not break down," he told The Associated Press on Monday. "That will be the short-term challenge to come."

European Council President Charles Michel, who chairs summits of prime ministers and presidents from the 27 EU nations, announced the video conference in a tweet, calling what will be the second meeting of its kind within two weeks.

"Containing the spread of the virus, providing sufficient medical equipment, boosting research and limiting the economic fallout is key," Michel said.

Michel called the summit shortly after he held talks with French President Emmanuel Macron, German Chancellor Angela Merkel and European Commission President Ursula von der Leyen. Macron's office said their conversation allowed them to make decisions about measures to take at the external borders of the EU which will be announced in the coming hours. No details were provided.

European Centre for Disease Prevention and Control figures released Monday show that 51,771 coronavirus cases have been reported in Europe, most in Italy, Spain, France and Germany. A total of 2 ,316 people have died, the overwhelming majority in Italy.

For most people, the virus causes only mild or moderate symptoms, such as fever and cough. For some, especially older adults and people with existing health problems, it can cause more severe illness, including pneumonia.

"Essential goods and medicines must be able to cross borders as smoothly as possible. This is a time for solidarity and cooperation," EU Health Commissioner Stella Kyriakides tweeted, after hosting a separate virtual meeting of the bloc's health ministers Monday.

The ministers agreed to start purchasing together protective equipment, testing kits and ventilators to help those member countries hardest hit, Kyriakides said.

EU finance ministers were also set to hold coronavirus talks by computer later Monday, as the disease and the efforts to combat it take their toll on the bloc's economy.

Worth also noted that the EU's limited financial means were a major obstacle in the response to the crisis and that deploying the medical aid needed across the bloc with a very restricted budget was a tall order.

"The total British NHS budget is larger than the EU's total budget for everything per year," he said. "At EU level, you don't have the means to sort out this problem."

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Sylvie Corbet in Paris contributed to this report.

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The Associated Press receives support for health and science coverage from the Howard Hughes Medical Institute's Department of Science Education. The AP is solely responsible for all content.

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