NBC: President Barack Obama challenged fellow world leaders in unusually blunt language Monday to act boldly on climate change or “condemn our children to a world they will no longer have the capacity to repair.”

In a forceful address, Obama opened the “GLACIER” conference in Anchorage, Alaska, by declaring: “We are not moving fast enough. None of the nations represented here are moving fast enough.”

That includes the U.S., which Obama said “recognizes our role in creating this problem and embraces our role in solving it.”

Obama is using the three-day GLACIER conference — it stands for Global Leadership in the Arctic: Cooperation, Innovation, Engagement and Resilience — as a way both to highlight the perils of global warming and to cement his environmental legacy. He directly attacked politicians who argue that climate change isn’t real, saying they “are on their own shrinking island.”

“The time to heed the critics and the cynics and the deniers is past,” the president said.

Unless the world acts more aggressively and more quickly, he said, “entire nations will find themselves under severe, severe problems: More drought. More floods. Rising sea levels. Greater migration. More refugees. More scarcity. More conflict.”

Related Citi report: slowing global warming would save tens of trillions of dollars