The spiritual leader of the world's Orthodox Christians has arrived on the Greek island of Spetses to host an environmental conference to seek backing from other religious leaders in a global campaign to take action against climate change.

Ecumenical Patriarch Bartholomew — dubbed the "Green Patriarch" for his support for environmental causes — inaugurated the two-day conference on Wednesday.

The meeting comes just over a year after President Donald Trump announced the withdrawal of the United States from the 2015 Paris climate agreement.

Senior environmental experts are attending the event on the island about 100 kilometers (60 miles) southwest of Athens.