Enron founder Kenneth Lay has told a Texas court that he was innocent of any wrongdoing and sought jurors' sympathy for the "enduring pain" he said the company's collapse caused him.

"By most standards I've been successful, way beyond my wildest hopes and dreams. I've not only pursued the American dream, I've achieved it. I guess you could say in the last few years I've achieved the American nightmare," he said.

He blamed the energy giant's troubles on former chief financial officer Andrew Fastow, who has pleaded guilty to fraud, and on the media.

He claimed that Enron's fundamentals were good but that negative media reports, after Mr Fastow's misdeeds were exposed, sapped market confidence in the company.

"There was this loss of confidence . . . It was increasingly based on confidence of the parties doing business with us and confidence of the financial market," he said.

Describing the hiring of Mr Fastow as the greatest mistake he made at Enron, Mr Lay said the former chief financial officer did a "tremendously brilliant" job of hiding his crimes from superiors.

"I've said before I accept full responsibility for everything that happened at Enron. Having said that, there's no way I could take responsibility for the criminal conduct that I didn't know about," he said.

Much of Mr Lay's testimony yesterday was devoted to defence questions about his childhood as a Baptist preacher's son and about his own family life, his children and grandchildren.

Mr Lay praised co-defendant Jeffrey Skilling, who faces more numerous and serious charges but appeared to shift some blame by saying that Mr Skilling was a "more hands-on" manager than himself.

"I'm very much of a decentralisation person. I've always tried to develop the organisation around the talent of the individuals. Let them spread their wings and see what they can do. I'm more of a delegator," Mr Lay said.

He said he had been deeply distraught by the company's collapse, particularly in view of the thousands of employees who lost their jobs and retirement savings.

Mr Lay portrayed himself as extremely distraught by the "hurt and destruction and pain" that came with Enron's collapse in 2001, including the loss of employees' jobs and retirees' life savings.

"I'm sure there's absolutely nothing in my life, including the loss of life of many of my loved ones, that even comes close to the same level of pain, and the same enduring pain, that has caused," he said.