Obama warns global recession makes climate change fight harder

President Obama warned Tuesday that the global economic recession could hinder the ability of countries to take necessary steps to combat climate change.

President Obama pledges the U.S. government's commitment to fighting climate change.

"We seek sweeping but necessary change in the midst of a global recession, where every nation's most immediate priority is reviving their economy and putting their people back to work," Obama told a U.N. summit on climate change. "And so all of us will face doubts and difficulties in our own capitals as we try to reach a lasting solution to the climate challenge."

Obama acknowledged that the United States has previously failed to recognize the magnitude of the climate change issue, and he pledged his government's commitment to developing clean energy sources and reducing greenhouse gas emissions that cause global warming.

"We understand the gravity of the climate threat. We are determined to act. And we will meet our responsibility to future generations," Obama said.

However, his speech lacked specific details on targets for greenhouse gas emissions and was received with polite applause.