The president drew chuckles when he added: "I want to be sure that facts are driving scientific decisions, not the other way around."

Obama said his administration would double the budget of key agencies, including the National Science Foundation and the National Institute of Standards and Technology.

"At such a difficult moment, there are those who say we cannot afford to invest in science. That support for research is somehow a luxury at a moment defined by necessities. I fundamentally disagree," Obama said.

"Science is more essential for our prosperity, our security, our health, our environment, and our quality of life than it has ever been," he said.