Barack Obama was forced to distance himself yesterday from his former pastor and religious mentor, who has made racially charged criticisms of Hillary Clinton and suggested that the terrorist attacks of September 11, 2001, showed that “America’s chickens are coming home to roost”.

The black liberationist theology of the Rev Jeremiah Wright, who retired last month from the Chicago church attended by Mr Obama, has previously barely flickered as an issue in the presidential race.

In the past 48 hours, however, after a week in which both Democratic candidates have had to jettison supporters for making controversial statements, Mr Wright has emerged as a significant problem for Mr Obama.

TV networks have constantly replayed videos of sermons in which the pastor, who married Mr Obama and baptised his children, denounces the United States. The campaign of John McCain, the Republican nominee-elect, began circulating material on the pastor yesterday and right-wing talk radio hosts devoted hours to the subject.

One video shows Mr Wright speaking after 9/11. “We have supported state terrorism against the Palestinians and black South Africans,” he said, “and now we are indignant because the stuff we have done overseas is now brought right back to our own frontyards.”

In another sermon he said that the Government “wants us to sing ‘God Bless America’ ” despite treating black people as second-class citizens. “No, no, no,” Mr Wright said, “God damn America!”

More recently, he has said that Mr Obama “knows what it means living in a country and a culture that is controlled by rich, white people; Hillary would never know that, Hillary ain’t never been called a nigger”.

Mr Obama’s campaign failed to answer repeated questions from The Times and other media organisations yesterday about whether Mr Wright was still a member of his AfricanAmerican religious leadership committee. Instead, he issued a statement categorically denouncing “inflammatory and appalling remarks [Mr Wright] made about our country, our politics, and my political opponents”.

Stressing that he had not been present when Mr Wright made the offending statements, Mr Obama said that he had become aware of them just over a year ago and had remained part of the church only because the pastor was retiring. He added: “He has never been my political adviser; he’s been my pastor.”

Previously, Mr Obama has described the man who brought him to religion 20 years ago as a “sounding board” who had offered private advice and joined him in prayer before he decided to run for president. The title of his autobiography, The Audacity of Hope, is taken from one of Mr Wright’s sermons.

At a meeting with a Jewish group in Ohio this month, Mr Obama said: “I don’t think my church is actually particularly controversial” as he compared Mr Wright’s controversial views to those of “an old uncle”.

Mrs Clinton’s campaign has so far declined to comment, possibly because of a three-minute conversation the two candidates were seen having in the Senate on Thursday. Aides said later that they had been discussing how to take some of the heat out of recent attacks.

There is, however, growing alarm within the Democratic Party over the apparent polarisation of voters along lines of gender, class and, especially, race in recent primaries. Mrs Clinton’s chief strategist, Mark Penn, suggested this week that if Mr Obama could not win over Pennsylvania’s largely white and heavily Catholic vote next month, he would not be able to win the general election in November.

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