"Off Target," "Broken Record," "Closing Window": the UN Environment Programme's flagship reports have been warning for years that emissions must fall faster to avoid dangerous climate impacts -- but is the world listening?

UNEP Executive Director Inger Andersen thinks so, pointing to progress made since the Paris Agreement a decade ago, but says nations must go further, and wean off fossil fuels.

The Danish economist, in Brazil for the marathon COP30 climate talks, is no stranger to the pitfalls of environmental diplomacy, having presided over tense plastic treaty talks that collapsed in August.

Andersen spoke with AFP on the sidelines of the UN's annual climate summit about finding common ground, the need for deadlines, and why she wishes the United States was present in Belem.

This interview has been edited for length and clarity.

Q: UNEP says the latest national climate pledges, or NDCs, make little difference to the global warming outlook this century. Are countries taking this crisis seriously?

A: "I think they are. We are seeing a degree of stretch in some of the NDCs -- but this stretch is not enough. The question is, do we just all give up and walk home? No. This is a time when we lean in."

Q: Greenhouse gas emissions keep rising, pushing up global temperatures. Do the climate COP summits need to more explicitly address the world's failure to curb emissions?

A: "A conversation around emissions is what we need to do -- and it is urgent. Having it on this formal agenda, or in another way, it is critical that we do not lose sight of the fact that the whole story has to end with a reduction, a phase out, a phase down, the transition away from fossil fuels, such that we don't have the emissions that we are talking about.

"We need to scale up the alternatives that can power our world, because you and I and the rest of the world are addicted to fossil fuels. Right now, our economies drive on it in many countries."

Q: Efforts to forge a global treaty on plastic pollution failed this year in Geneva. UNEP facilitated these talks and pushed for a strong result quickly. Were you too ambitious?

A: "I was one of the ones who pushed for a deadline -- let's get it done in two years. Now did I know that we wouldn't get it done? That was a high likelihood. It took us 17 years to get to BBNJ (the High Seas Treaty). It took 21 years to get to even a target on climate. But we don't have 21 years or 17 years for plastic, because it's everywhere.

"We have had six meetings in two and a half years. What happens (next) is what happens in any negotiations -- we take another round. And sometimes when you're down and out, that's when it focuses the mind."

Q: With that experience in mind, what advice do you have for diplomats here at COP30 as they navigate these difficult climate negotiations?

A: "At this point when geopolitics is complex and when there are tensions in the global multilateral system, it's really important to remember that we are all here for the same reason. Do we have different interests? Maybe. Are they pulling in different directions? At times, yes. But does anyone not want to solve the plastic or the climate crisis? I don't think so."

Q: There are no federal US government officials here in Belem. Given Washington's conduct in recent environmental talks, is COP30 better off without them?

A: "No, in multilateralism we would like to see all 193 member states present. Of course, we respect the decision of an elected government. That's a sovereign decision. But we certainly would like to see a presence irrespective of the positions that individual governments may take.

"And just to make very clear that the US was present in Geneva, and I will not put at their feet what transpired. It was a collective failure and I think everybody -- including the United Nations -- has to look at what can we do better next time around."