The Archbishop of Canterbury has called on political parties not to exploit people's fears in an effort to win the general election.
Dr Williams called for policies to protect the environment
In an open letter to party leaders, he complained "familiar anxieties" over terror, asylum and immigration already looked like featuring in campaigns.
Such negativity intensified the "disillusion and disaffection of a large part of the electorate," he said.
Later, Dr Rowan Williams said that causing anxiety over asylum was racist.
Speaking on BBC Two's Newsnight programme, he said: "I think that every time there's an election on the horizon there is this feeling that the way to win it is to frighten people.
"I just don't think that's good enough - it certainly isn't capturing the imagination of the people."
Conservative posters have been put up declaring "it's not racist to impose limits on immigration" and leader Michael Howard has stressed his immigrant background.
Asked if this was racist, Dr Williams told Newsnight: "It's racist to whip up the kind of anxiety that can be so easily generated on the subject."
This presented asylum seekers as an "uncontrollable menace", he said.
In his open letter to the leaders of the main political parties Dr Williams attacked the "collective lack of international responsibility about the environment".
He also said that prisons were "no answer" to "addressing offending behaviour" and called for more money to be spent on educating offenders.
And he said his call for policies to promote stable families and marriages was not "middle class, middle England nostalgia" but "life and death".
"The climate of chronic family instability, sexual chaos and exploitation, drug abuse and educational disadvantage is a lethal cocktail," he added.
But Conservative co-chairman Liam Fox said it was the people who decided election issues and "not the politicians, not the churchmen or anyone else".
"The voters want to talk about their fear of a crime in a country where violent crime has increased dramatically," he said.
"They want to talk about immigration at a time when immigration has spiralled out of control.
"Politicians have a duty to talk about those issues."
Chancellor Gordon Brown welcomed Dr Williams' comments.
"I'm grateful to the Archbishop of Canterbury, as we all should be, for reminding us there are very big and important issues about the values that our country represents, about the condition of our country and the need for social cohesion."
Liberal Democrat leader Charles Kennedy said: "The Archbishop surely speaks for millions when he says let's concentrate on the positive in this election campaign, political parties putting forward honest choices."