Richard Goldstone, the lead author of a United Nations report that found evidence of war crimes committed by Israel and Hamas during last winter’s Gaza war, challenged the Obama administration in an interview broadcast Thursday to explain what it has called serious concerns about his report.

In the interview on Al Jazeera, Mr. Goldstone, a South African jurist, said that the official American response to the 575-page report had been ambivalent. The Obama administration, he said, “joined our recommendation calling for full and good-faith” domestic investigations of the alleged crimes in both Israel and Gaza, “but said that the report was flawed.”

“But I have yet to hear from the Obama administration what the flaws in the report that they have identified are,” Mr. Goldstone said. “I mean, I would be happy to respond to them, if and when I know what they are.”

He added, “Of course I’m concerned and would like to engage with the Obama administration, at least informally.”

The report found evidence that some Israeli soldiers had intentionally killed Palestinian civilians during the three-week conflict in violation of the laws of war. It described the Israeli military assault on Gaza as “a deliberately disproportionate attack designed to punish, humiliate and terrorize a civilian population, radically diminish its local economic capacity both to work and to provide for itself, and to force upon it an ever increasing sense of dependency and vulnerability.”

It also said there was evidence that the Palestinian militant rocket attacks on towns in southern Israel constituted war crimes.

The report’s recommendations were officially endorsed last week by the Human Rights Council in Geneva, which has forwarded the document to the United Nations General Assembly and Secretary General Ban Ki-moon. The United States joined five European nations in voting against the resolution that endorsed the report, and Israeli officials have lobbied hard to discredit it.

“People generally don’t like to be accused of criminal activity, so it didn’t surprise me that there was criticism, even strong criticism, and it has come from both sides,” Mr. Goldstone said in the interview. “But I do regret the extremes to which some of the criticism has gone and the fact that it has been so personalized.”

He then lashed out at his detractors, saying, “I’ve no doubt, many of the critics — I would say the overwhelmingly majority of the critics — haven’t read the report. And, you know, what proves that, I think, is the level of criticism doesn’t go to the substance of the report. There still haven’t been responses to the really serious allegations that are made.”

Obama administration officials have made more detailed criticisms of the report, usually contending, as did Douglas M. Griffiths, the American delegate to the Human Rights Council, that it was unfair to Israel.

Explaining his vote against endorsing the report, Mr. Griffiths said that, “While Justice Goldstone acknowledged Hamas’s crimes, in examining Israel’s response sufficientweight was not given to the difficulties faced in fighting this kind of enemy in this environment.”