Barack Obama has resigned his 20-year membership in the Trinity United Church of Christ in Chicago in the aftermath of inflammatory remarks by his longtime pastor, the Rev. Jeremiah Wright, and more recent fiery remarks at the church by another minister.

Rev. Jeremiah A. Wright, Jr., pastor of Chicago's Trinity United Church of Christ and the former pastor of Democratic presidential hopeful Sen. Barack Obama, as seen in April . (J. Scott Applewhite/Associated Press)

Obama campaign communications director Robert Gibbs said Obama had resigned from the church "over the last few days."

Campaign aides said they weren't immediately certain how the resignation took place, whether by letter or in some other fashion, and were trying to find out.

Messages left for a church spokeswoman in Chicago were not immediately returned Saturday afternoon.

The development came as Obama campaigned in South Dakota.

Obama said he disagreed with Wright but initially portrayed him as a family member he couldn't disown. The preacher had officiated at Obama's wedding and been his spiritual mentor for about 20 years.

But six weeks after Obama's well-received speech on race, Wright claimed at an appearance in Washington that the U.S. government was capable of planting AIDS in the black community.

He also praised Nation of Islam leader Louis Farrakhan and suggested that Obama was acting like a politician by putting his pastor at arm's length while privately agreeing with him.

Obama denounced those Wright comments as "divisive and destructive."

Comments by Wright inflamed racial tensions and posed an unwanted problem for Obama, front-runner for the Democratic presidential nomination, as he seeks to wrap up the nomination.

More recently, racially charged remarks from the same pulpit by another pastor, the Rev. Michael Pfleger, kept the controversy alive and proved the latest thorn in the side of Obama.

Pfleger mocked Obama rival Hillary Clinton as a guest speaker at Obama's church. Although Obama condemned comments by both Wright and Pfleger, the controversy has persisted.

For months, Obama has been hamstrung by the rhetoric of Wright, whose sermons blaming U.S. policies for the Sept. 11 attacks and calls of "God damn America" for its racism became fixtures on the Internet and cable news networks.

On Thursday, Obama was again forced to reject Pfleger.

Obama made it clear he wasn't happy with the comments — in which Pfleger pretended he was Clinton crying over "a black man stealing my show" — and said he was "deeply disappointed in Father Pfleger's divisive, backward-looking rhetoric, which doesn't reflect the country I see or the desire of people across America to come together in common cause."

Republican John McCain also has had his woes with religious leaders.

Earlier this month, McCain rejected endorsements from two influential but controversial televangelists, saying there's no place for their incendiary criticisms of other faiths.

McCain spurned the months-old endorsement of Texas preacher John Hagee after an audio recording surfaced in which the preacher said God sent Adolf Hitler to help Jews reach the promised land. McCain called the comment "crazy and unacceptable."

He later repudiated the support of Rod Parsley, an Ohio preacher who has sharply criticized Islam and called the religion inherently violent.