Unlike any president of modern times, the Democrat has singled out non-believers as an important part of the nation's demographic mix. Secularists are impressed, the Christian right less so.

"We are pleased that he recognises that we exist," said Ron Millar, acting director of the Secular Coalition for America.

"So we do see this as an important first step," he said.

"But there's a lot of work to do to reclaim our secular character, after the amount of influence the religious right has had over the last eight years."

Obama on Thursday announced a new White House Office of Faith-Based and Neighborhood Partnerships, overhauling the former Bush administration's deeply contentious initiatives to bring religious groups into social policy.

Obama, a Christian who has long called for progressive liberals to shed their mistrust of religion, appealed to all worshippers to band together and assist society's most vulnerable at a time of acute economic crisis.