Former Mossad chief Meir Dagan and Environmental Protection Minister Gilad Erdan traded barbs on Sunday during a heated panel at the Jerusalem Post Conference in New York.During the panel, the discussion turned to comments made by former Shin Bet (Israel Security Agency) director Yuval Diskin, who said last weekend that he has no confidence in Prime Minister Binyamin Netanyahu and Defense Minister Ehud Barak to conduct a war. Erdan criticized Diskin, saying that "In order to save Israel, [Diskin] should have resigned, instead of waiting five years and making his comments." Dagan, who earlier on Sunday on the sidelines of the conference expressed his support of Diskin, saying he was a serious man and spoke his own "internal truth." "Don't hide behind theories or things that Yuval Diskin said," Erdan retorted. "You said he's a serious guy. How can a serious guy say that '[Netanyahu and Barak] are not the messiah.' Who said they're the messiah?" Erdan then claimed that Diskin decided to speak out against Netanyahu because the person he wanted to succeed him was not given the post."You are a liar," Dagan responded.Former IDF chief of staff Lt.-Gen. Gabi Ashkenazi also defended Diskin on Sunday at the conference. "I know Diskin and he spoke what was on his heart out of genuine concern," Ashkenazi said on the sidelines of the conference.Speaking at a conference Friday, Diskin said Barak and Netanyahu are are guided by “messianic” impulses and are lying about the projected effectiveness of an Israeli strike on Iran.“There’s a false image being presented to public and that’s what bothers me,” Diskin said, speaking to the small Majdi Forum in Kfar Saba.“They [Netanyahu and Barak] are giving the sense that if Israel doesn’t act, Iran will have nuclear weapons. This part of the sentence apparently has an element of truth. But in the second part of the sentence, they turn to the – sorry for the expression – the ‘stupid public’ or the layman public... and tell them if Israel acts, there won’t be [an Iranian] nuclear program. And that’s the incorrect part of the sentence,” Diskin said.The former Shin Bet chief came under heavy criticism once the remarks were picked up by the media, with sources close to Barak and Netanyahu accusing him of being bitter after he was not chosen to head the Mossad.Dagan too has come under fire for criticizing the current leadership's approach to the Iranian threat, reportedly saying last year that an attack on Iran's nuclear reactors "would be foolish."“Anyone attacking Iran needs to understand that it could start a regional war which will include missile fire from Iran and Hezbollah in Lebanon. The Iranian problem must be made an international problem, and we must continue to work to delay the nuclear program,” he said.Yaakov Lappin contributed to this report.