In an effort to pressure the multinational fossil fuel giant BP to stop oil and gas exploration that is "fueling a climate emergency," Greenpeace activists early Monday blockaded the company's London headquarters with massive metal containers weighing several tons each.

According to The Guardian, two Greenpeace activists are "encased in each of the five containers with enough provisions to last at least a week. Another 15 activists are occupying the top of the boxes after abseiling down the side of the building."

"We're shutting down BP's HQ because business as usual is just not an option," Greenpeace U.K. activist Paul Morozzo said in a statement. "BP is fueling a climate emergency that threatens millions of lives and the future of the living world. The science is clear: we must stop searching for new oil and gas if we want a livable planet. BP must clean up or clear out."

Activists are blocking the entrances to BP’s London HQ. They have set up camp inside specially designed containers. BP can’t continue as if it’s business as usual in this #ClimateEmergency we’re in. #BPshutdown pic.twitter.com/9FaaLMajo5 — Greenpeace UK (@GreenpeaceUK) May 20, 2019

Speaking to The Guardian by phone from inside of one of the containers—which were put in place using cranes early Monday morning—Morozzo said the metal boxes were designed to be impossible to move without harming those on the inside.

"For too long, BP and the oil industry have paid lip service to climate action while lying and lobbying against it behind the scenes and spending billions scouring the world for more oil and gas," said Morozzo. "The reality is that BP's whole business plan is a heavy bet against our hopes to avoid a climate catastrophe and must change."

Five containers are blocking @BP_plc's head office, specially designed and weighing several tonnes each. Activists are encased inside and they won't be easy to move #ClimateEmergency #BPShutdown pic.twitter.com/queEYRRtbx SCROLL TO CONTINUE WITH CONTENT Never Miss a Beat. Get our best delivered to your inbox.





— Greenpeace UK (@GreenpeaceUK) May 20, 2019 Immy is inside one of the boxes as part of our #BPShutdown. What’s it like being encased in heavy-duty container? #ClimateEmergency pic.twitter.com/fJAWpH1fON — Greenpeace UK (@GreenpeaceUK) May 20, 2019

The blockade of BP headquarters comes just 24 hours ahead of the company's annual general meeting.

Paula Radley, a Greenpeace activist currently encased inside one of the metal containers, wrote in a blog post published Monday that companies like BP "need to stop exploring for oil or wind down their business."

"Future generations will look back at this time and ask why we didn't do more, and I will be able to say I did everything I could," Radley wrote. "The way that companies like BP operate is no longer acceptable. BP are just motivated by their profits, regardless of the damage they're doing. And their time has come to an end. We do have a future—but BP's not in it."