BRUSSELS — After months of virtual diplomacy hampered by mute-button troubles, spotty ­Internet connections and long-distance misunderstandings, European leaders plan to gather here Friday for their first in-person summit since covid-19 shut everything down.

They will be taking elaborate precautions to reduce the risk.

The 27 country leaders and four top European Union officials will meet not around their ordinary ring-shaped table but in a vast hall designed to seat 330. The room, at the European Council building, will use only filtered fresh air that won’t be recycled. It will be cleaned at every break, as will door handles and translation headsets. The leaders won’t have to wear face coverings during their discussions but must mask up as they come and go.

Outside, a doctor will be standing by in case anyone starts to feel ill. The country delegations — the assistants and advisers who mill around while the government leaders meet — have been downsized from the typical 19 people each to six.

European diplomats, and the 446 million E.U. citizens, will cross their fingers and hope their leaders stay safe.

“Around the table, can you guarantee there’s not a superspreader?” rhetorically asked one diplomat — who used a swear word when imagining the worst-case scenario of all of Europe’s leaders getting sick at once. But the diplomat, who spoke on the condition of anonymity to discuss sensitive planning, observed that most heads of government are frequently tested for the coronavirus, reducing the chance any of them would show up with it in their systems.

For all the complications, there’s relief that Europe has gotten its coronavirus outbreak under control to the extent that it’s possible to consider meeting in person. Just as videoconferencing has turned out to be a frustrating substitute for bricks-and-mortar schooling, so too has it proved a serious setback to diplomacy.

“If you need to get compromise, if you need a solution, then it is almost impossible to do it by digital diplomacy,” said Latvian Foreign Minister Edgars Rinkevics, who marveled during a trip to Brussels this week — his first venture outside the Baltics since March — at how shut down Belgium felt compared with his own relatively coronavirus-free nation. “You need to meet, you need to be able to gather like-minded people. We’ve lost four months.”

The challenge has been especially sharp for the European Union, a freewheeling agglomeration of 27 independent nations that under ordinary circumstances come together in Brussels — sometimes as often as several times a week — to coordinate issues as lofty as nuclear diplomacy and as fine-grained as cellphone charges.

Diplomats say their work has been hindered without the ability to easily step aside to whisper out possible compromises.

“The problem with Zoom is that it reduces the essence of what we’re doing to only the meeting,” said a Brussels-based E.U. diplomat, who spoke on the condition of anonymity to talk freely about the sausage-making. “Diplomacy is like an iceberg. There’s so much work being done underneath the surface.”

The diplomat blamed some of the early E.U. pandemic missteps, such as Germany and France’s short-lived ban on exporting masks and hospital gowns to their neighbors, on the absence of in-person discussions. Brexit negotiations, which have also been mostly virtual, are likewise struggling to make progress, since both sides need to make painful compromises that would be politically toxic if leaked publicly before being finalized.

“The whole machine stalled” during the pandemic, the diplomat said.

Europe’s leaders last gathered Feb. 21. The ambassadors each E.U. country posts to Brussels continued meeting in person. But they aren’t empowered to make the truly thorny decisions that can lead to the success or failure of politicians back home, so their meetings couldn’t make up for their bosses’ absence.

Video calls between leaders and ministers ran into multiple problems. Initially, simultaneous translation wasn’t available, slowing down communication. Frozen screens and other technical glitches could plague a single meeting as many as 15 times, one diplomat said. Children and pets sometimes wandered across the screen when lower-level diplomats were doing meetings from home. And it turns out that senior policymakers are just as prone as the rest of us to forget to unmute their microphones — or, more embarrassingly, to forget to turn them off.

Among other challenges, Latvia’s Rinkevics said, it has been far harder to guarantee the confidentiality of conversations that take place virtually. For example, one discussion about E.U. relations with a non-E.U. country was supposed to be confined to foreign ministers alone. It leaked almost in real time to policymakers from that country, he said.

“If you want to have a truly candid exchange, in-person is better,” he said.

The leaders meeting Friday and Saturday will haggle over a potential pot of $2 trillion, a combination of their coronavirus economic rescue plan and the ordinary E.U. budget that sets up winners and losers for the next seven years. It turns out that it is nearly impossible to reach a deal through videoconferencing.

The first in-person meeting of E.U. foreign ministers Monday served as something of a test run. The agenda didn’t lend itself to easy compromise: Policy toward China and Hong Kong, as well as Turkey, was under discussion, topics on which E.U. members have sharp differences.

“It’s a good thing that we could consider all of them personally,” said E.U. foreign policy chief Josep Borrell, 73, who wore his blue medical mask for some of the five-hour discussion.

Meeting in person “helps a lot to discuss,” Borrell said.

Still, six of the 27 foreign ministers didn’t show up, with some stymied by the inconvenience of traveling across a continent where many flight connections have evaporated. Of the ministers who did, many seemed uncomfortable as they chatted, masked, ahead of the meeting. For most, it was their first foreign travel since the beginning of the pandemic, and they appeared to be struggling to bridge old habits to new necessities.

Bulgarian Foreign Minister Ekaterina Zakharieva fanned her thick black cloth mask with her hand. Spanish Foreign Minister Arancha González traced a smile over her blue medical mask. Croatian Foreign Minister Gordan Grlic Radman wore a mask in his country’s red-and-white checkerboard motif. Once the proceedings were underway, the masks came off.

Swedish Foreign Minister Ann Linde, who has the misfortune of representing the most infected member of the European Union, relative to population, appeared to be happy to get out of Stockholm.

Belgium recommends but doesn’t require quarantines for travelers from Sweden. “Essential travel” — which presumably includes a meeting of foreign ministers — is allowed.

“It’s very, very nice to be able to meet my colleagues in person again,” Linde said.

Quentin Ariès contributed to this report.