Image copyright Getty Images Image caption UN climate negotiators hope Ivanka Trump will heed their pleas on the Paris climate accord

Among the diplomats meeting here in Bonn, there's a recognition that the person who's really key to the future progress of climate talks is not in Germany but in the White House some 6,500km (4,000 miles) away.

It's not you Mr Trump, it's your official first daughter!

One delegate here trilled: "What are we going to do about Ivanka?"

He wasn't alone. In most of the conversations I've had here in Bonn, one name is mentioned with a nodding mixture of reverence and hope.

For rich and poor countries, she's seen by many as the best bet for keeping the US in the Paris climate agreement.

But is this the true state of affairs? Or just the delusion of delegates, who, in fairness, don't get out much.

"It's crazy times, and we're trying to influence with all the tools and tactics at our disposal," said Liz Gallagher from environmental think tank, E3G, and a long time participant in these talks.

Image copyright Getty Images Image caption Many believe that Ivanka represents the best way of influencing her father on climate questions

"My colleagues tell me that Ivanka has been going around and backing up the Paris agreement, going round speaking to cabinet members and trying to get them onside on this issue," she said.

"She's been doing more so than others like (Secretary of State) Rex Tillerson who have said they're okay with Paris, but haven't actively championed it."

Call the White House!

It's not just the people on the ground here who are fervently trying to get a message to Ivanka,

Environmental campaigners around the US and the world are being urged to get in touch with the White House and try to speak to the the woman who has reportedly been put in charge of a review of US climate policy.

"Use these talking points for your call, and be sure to tell the operator you're leaving a message for Ivanka Trump," said the instructions sent out to supporters by the National Resources Defense Council last week.

"Hi, I'm calling with the hope that you'll do everything in your power to convince your father not to abandon the Paris climate agreement; You call yourself a 'moderating influence' on the White House. This is your chance to show it," says the email.

Many believe that the postponement of a US decision on future participation in the Paris agreement until after the President returns from the G7 meeting in Italy at the end of May is a good thing.

The more delay, the more chance of finding new ways of getting the message to others in the Trump team.

"There are very strong voices of reason in the US," said former lead negotiator for Colombia, Paula Caballero, who's now with the World Resources Institute.

"We are already seeing articles from important people who contributed to the Trump campaign who said they didn't support Paris but now they do."

"They are starting to understand the underlying arguments of national self interest that could and should compel the Trump administration to stay in Paris."

Some commentators believe that the President is now in an optimal position - everyone is waiting on him, no-one wants to upset him. He doesn't really have to do anything.

However that situation is unlikely to last more than a few months. As one delegate said, it will soon be time for him to "poop or get off the pot."

Image copyright Aaron P. Bernstein Image caption EPA administrator Scott Pruitt is said to be in favour of US withdrawal from Paris

"People will start to get Trump fatigue," said Liz Gallagher.

"The leverage he now has through this indecision can only last for a few months, because after that people will put him in a box, and say we will continue moving on."

One option that's cropping up more and more is the idea of a face-saving compromise. After meeting with other world leaders, including the Pope, it's possible that President Trump may say he's going to stay in and "re-negotiate" the Paris deal.

People may well be able to row in behind that.

"Mr Trump is a businessman and he knows that to be successful you need to understand what everyone else is doing," said Paula Caballero.

"That's what's happening in Bonn right now, that's what's going to be happening for the next 18 months."

"A seat at the table buys you the ability to be able to influence how those rules are designed."

The delegates here hope that logic and reason like this will triumph and President Trump will see the light.

But they're certain to keep on quietly messaging Ivanka.

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