WASHINGTON ? Controversial news anchor Lou Dobbs abruptly quit CNN on Wednesday, announcing at the top of his evening broadcast that it would be his last.

Dobbs, who has worked at CNN since its inception nearly 30 years ago, began his career as a business reporter and has evolved into an outspoken commentator with a conservative, populist bent.

Many of his views are seen as out of step with CNN's attempt to seek a middle ground in its reporting and avoid the allegations of bias which have hit rival Fox News.

Dobbs, 64, has come under fire for his heated attacks on illegal immigration and for repeatedly discussing on his radio show far-fetched, right-wing allegations that President Barack Obama is not a legitimate US citizen.

Dobbs did not say what he planned to do after leaving the network but indicated that he wants to get more politically engaged.

"Over the past six months it's become increasingly clear that strong winds of change have begun buffeting this country and affecting all of us, and some leaders in media, and in politics and business have been urging me to go beyond the role at CNN and to engage in constructive problem-solving as well as to contribute positively to the great understanding of the issues of our day," he told viewers.

Dobbs said he talked with CNN President Jonathan Klein, who agreed to release him from his contract.

Klein called Dobbs "a valued founding member of the CNN family," and said in a statement that Dobbs "fearlessly and tirelessly pursued some of the most important and complex stories of our time, often well ahead of the pack."

Dobbs cited a number of issues that he feels are "now defined in the public arena by partisanship and ideology rather than by rigorous, empirical thought" and vowed to work to "change that as best as I can."

"And as for the important work of restoring inspiration to our great free society and our market economy, I will strive as well to be a leader in that national conversation," Dobbs said.