What’s it like to be an American at the UN climate talks?

President Donald Trump has said he’s pulling the US out of the Paris climate agreement. But UN rules don’t allow the country to exit the agreement until 2020.

That means US delegates, a faction of “unofficial delegates” and American observers are all attending the negotiations and hundreds of side events held in Bonn, Germany, this week and next.  

With the US as the only country in the world that doesn’t plan to remain in the accord, things are bound to get awkward.  

Related: Is China really stepping up as the world’s new climate leader?

“It feels a little bit like someone who’s come to the party and you’ve crashed it and you’re afraid to open your mouth,” observer Sarah Diefendorf told The World. “The minute you start talking they’re going to know you don’t belong here. It feels a little ghostly, almost.”

Diefendorf is the director of the Environmental Finance Center West, a California-based nonprofit that works to build capacity in indigenous and low-income communities for dealing with climate change.

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“Most of the time, I don’t even really want to ask a question,” Diefendorf says from Bonn. “I’m certainly not going to offer an opinion because I’m an American, I don’t really have a right to provide any input.”

Diefendorf is among the thousands of observers from environmental groups, nonprofits, religious organizations and businesses that participate in the events held around the annual United Nations Conference of the Parties, or COP, every year.

This year’s summit, held Nov. 6-17 in Bonn, is the next step forward in implementing the Paris accord, the agreement between nearly 200 countries to cut carbon emissions.

Delegations from member countries will work on the Paris “rule book.” Due to be completed next year, the rule book will dictate how countries will report their carbon emissions, how the international community will verify them and a host of other details. Attendees will also lay the groundwork for the beginning of a dialogue in 2018 on how individual countries can cut carbon emissions even more than they’ve already planned.

This week, Syria announced it would join the Paris accord, leaving the US the only country with plans to remain outside the agreement.   

Related: Pulling out of Paris, Trump says climate deal ‘punishes the United States.’ Really?

A coalition headed by California Governor Jerry Brown and former New York City Mayor Michael Bloomberg is styling itself as a sort of unofficial delegation at the COP. The group of state and local officials and business leaders hope to deliver the message that sub-national actors in the US remain committed to the Paris agreement.

The group launched its program of events outside the official negotiation zone today.

Diefendorf says so far, that unofficial delegation hasn’t been getting much attention in Bonn. But her interactions with attendees from other countries at the summit have largely been positive.

“We appreciate it, you know, because you walked in the door thinking, 'My God, will they hate us?'” says Diefendorf. “What are they going to think of us?”

The official US delegation is made up largely of career civil servants who are expected to help work through the technical details of the agreement’s implementation, even as the US plans to back out of it.   

There were early concerns that the delegation may act obstructively and slow down the talks, but watchers say so far there are no signs that’s happening.

The Trump administration has received criticism, however, for sending administration officials to talk at a panel promoting fossil fuels as part of the solution to climate change.