Hollywood actress Jane Fonda
Hollywood actress Jane Fonda Image Credit: AP

Actor and activist Jane Fonda on Monday warned that humanity is "losing the ocean," as two weeks of negotiations begin at the United Nations on a treaty to protect the high seas.

"The ocean provides us with 50 percent of our oxygen, and it feeds billions of people - and it's dying," the 85-year-old American icon told AFP in an interview.

She is in New York to deliver a petition with more than 5.5 million signatures to Rena Lee, chair of the high-stakes talks which many hope will finally, after 15 years, result in a treaty aimed at protecting and preserving vast ocean areas.

The petition, which Fonda handed over Monday evening, calls for a "strong" treaty.

"I have children, I have grandchildren and I just want to spend every single possible moment that I can as long as I'm still alive, to not allow us to destroy the planet," Fonda told AFP.

Later at a reception, she said there is a "ray of hope" as the talks begin.

"We've never been so close and momentum has never been so high," she added.

"We need a global ocean treaty and we need it now.... It is at our own peril that we delay any further," she added, describing the ills plaguing the oceans, from plastic pollution to overfishing, warming, acidification and oil spills.

"I urge you as a mother, a grandmother and a citizen of this world: Set aside the politics, the greed, the special interests and the inertia that tends to drag big bold ideas into the ground," she said.

"Let's get this done."