French President Emmanuel Macron today warned that global plastics pollution was a "time bomb", as diplomats began five days of talks in Paris to make progress on a treaty to end plastic waste.

Representatives of 175 nations with divergent ambitions met at the UNESCO headquarters with the aim of making progress towards reaching, by next year, a historic agreement covering the entire plastics life cycle.

As the talks opened, the head of the negotiations Gustavo Meza-Cuadra Velazquez said the challenge was "immense, as we are all aware here, but it is not insurmountable"

"The world's eyes are on us," he said.

Macron urged participating nations to put an end to today's "globalised and unsustainable" production model, where richer countries export plastic waste to poorer ones.

"Plastic pollution is a time-bomb and at the same time already a scourge today," he said in a video message, adding that the fossil-fuel based material posed a risk to global warming goals, as well as biodiversity and human health.

He added that the first priorities of the negotiations should be to reduce production of plastics and to ban "as soon as possible" the most polluting products like single use plastics.

The stakes are high, given that annual plastics production has more than doubled in 20 years to 460 million tonnes, and is on track to triple within four decades.

Two-thirds of this output is discarded after being used once or a few times, and winds up as waste. More than a fifth is dumped or burned illegally, and less than 10 percent is recycled.

The head of the UN Environment Programme Inger Andersen told the delegates that a throwaway plastic culture was "gushing pollution galore, choking our ecosystems, warming the climate, damaging our health" and that the most vulnerable were the hardest hit.

"Only elimination, reduction of, a full lifecycle approach, transparency and a just transition, only those can bring success because the truth is that we cannot recycle our way out of this mess," she told delegates to loud applause.

In February 2022, nations agreed in principle on the need for a legally binding UN treaty to end plastic pollution around the world, setting an ambitious 2024 deadline.

The Paris meeting, which runs to June 2, is the second of five sessions in the process.

Policy actions to be debated during the talks include a global ban on single-use plastic items, "polluter pays" schemes, and a tax on new plastic production.

Environmental groups are encouraged that global plastics pollution is finally being tackled, but are concerned the treaty may not include targets to reduce overall plastic production.

"There is a consensus on the issues at stake and the will to act", Diane Beaumenay-Joannet, an advocate at the Surfrider Foundation, told AFP.

Environmentalists have also raised concerns about the influence of industry lobbying on the talks.

Plastics are everywhere: packaging, clothing, construction materials, medical tools, even diapers.

In nature, microplastics have been found in ice near the North Pole and inside fish navigating the oceans' deepest, darkest recesses.

In humans, microscopic bits of plastic have been detected in blood, breast milk and placentas.

Plastic also contributes to global warming: it accounted for 1.8 billion tonnes of greenhouse gases in 2019, 3.4 percent of global emissions, a figure that could more than double by 2060 according to the OECD.

Host country France organised a ministerial summit on Saturday with 60 countries to kick-start the talks.

"If we don't act now, by 2050 there will be more plastic than fish in the oceans", said French Foreign Minister Catherine Colonna.

Velazquez called on delegates to put aside differences to work towards an agreement that is fair "by essence, and effective by necessity".

There are already concerns about divisions among the countries.

A so-called High Ambition Coalition of 50 nations led by Rwanda and Norway, includes the European Union, Canada, Chile and –- as of a few days ago -- Japan.

But many countries are reluctant to aim for absolute cuts in production, insisting that recycling and better waste management is the answer.

These include China, the United States, Saudi Arabia and other OPEC countries, all of whom have large petrochemical industries.

The talks will also see the same tensions between rich and developing countries that bedevil UN talks on climate and biodiversity, especially around development aid, technology sharing and access to financing.

"Developed countries -- the biggest consumers and the biggest polluters -- have their products produced in other countries, and send their waste there too," said Beaumenay-Joannet.