A short drive from the United Nations complex in Nairobi where talks on a global plastics treaty are taking place this week is Kenya's biggest landfill - a mountain of garbage, carpeted in single-use plastic.

The equivalent of 30 trucks of throwaway plastic packaging, bags and containers are tipped on to Dandora dump daily, according to official data, a trend set to worsen with global plastic pollution forecast to double over the next decade.

This global waste crisis, which is destroying habitats, killing wildlife and contaminating the food chain, has sparked calls for radical action in a treaty billed as the most important environmental pact since the Paris Agreement.

"Our expectation is that when the treaty is signed, countries commit to stop the production of such plastics," Hibrahim Otieno, a local environmental official told Reuters at the dump site.

Otieno is not alone. Three in four people said they wanted single-use plastics banned as soon as possible in a study released this month ahead of the treaty talks.

But how the treaty will tackle single-use plastic production and use is set to be one of the thorniest issues in the talks, according to officials involved, as well as what elements of it will be legally binding and how it will be financed.

Behind-the-scenes, powerful oil and chemical companies who manufacture plastics have been urging governments to reject provisions that could curb their business, a Reuters investigation earlier this month revealed.

Industry executives and environmental pressure groups have been in Nairobi since last week observing hours of technical-level discussions on the pact and meeting with officials on the sidelines to press their case on key issues.

"This is not an anti-plastics treaty," Espen Barth Eide, president of the United Nations Environment Assembly which is hosting the talks in Nairobi, told Reuters. "We are not sort of after their product as such, but we want to bring it into a much more viable, circular economy."

Political representatives arriving on Monday must now approve the framework drafted by their technical experts and launch an intergovernmental negotiating committee (INC) to broker a final deal.

Those negotiations are expected to take at least another two years to complete, but the framework agreed in Nairobi is seen as crucial in ultimately determining the treaty's success.

"If we don't get the right formulation, the INC will be shackled and limited in what elements they can consider," said Christina Dixon of the Environmental Investigation Agency, one of the campaigners participating in the talks.