ISTANBUL — Muslim scholars and environmental advocates from about 20 countries on Tuesday called for a global phase-out of greenhouse gas emissions by midcentury, joining a chorus of religious leaders urging the world to take strong action against global warming.

Participants in a seminar in Istanbul said it was the first declaration of its kind from Islamic leaders, a voice many say has been missing from the debate on global warming.

The move comes two months after Pope Francis’ encyclical on climate change and other environmental issues and ahead of a key U.N. climate conference in Paris in December, where world leaders are supposed to adopt a landmark agreement to fight climate change.

“I think this declaration will incentivize ambitious actions and spur the Muslim world, especially the oil-producing countries,” said Mohamed Adow, a Kenyan advocate for climate action who attended the seminar.

Organizers said the declaration was “in harmony” with the pope’s message and supported by the Pontifical Council on Justice and Peace.

About 60 delegates adopted the declaration at the end of the seminar, including leading clerics from Indonesia, Uganda, Lebanon and Bosnia.

However, some influential Islamic leaders were absent, including Turkey’s top cleric, who didn’t even send a representative.

It remains to be seen whether the message from the scholars is repeated by imams in mosques across the Muslim world.

“Some of them are hopelessly out of touch on this,” said Fazlun Khalid of the Britain-based Islamic Foundation for Ecology and Environmental Sciences, which organized the conference together with the Islamic Relief charity.

The declaration urged rich countries and oil-producing states to lead the way in phasing out greenhouse gas emissions “no later than the middle of the century.”

The burning of oil, coal and gas is the main source of such emissions.

Climate activists are calling for a zero emissions goal to be included in the Paris agreement but face resistance from major oil-producing countries, including in the Middle East.