VATICAN CITY (AP) — Pope Francis is warning oil executives that a "radical energy transition" to clean, low-carbon power sources is needed to stave off the effects of a rapidly warming planet.

Francis told the leaders at a Vatican summit Friday that there was still time to avoid the worst effects of climate change but that "prompt and resolution action" is required.

The meeting marked the second year that Francis has invited oil and financial sector executives to the Vatican to impress upon them his concern that preserving God's creation is one of the fundamental challenges facing humankind today. The agenda included talks about energy transition, carbon pricing and transparency in reporting climate risk.

Outside the summit a half-dozen protesters held up signs urging the executives to listen to the pope.