An Israeli peace activist who has been instrumental in talks with Hamas in the past said Thursday that Israel may have destroyed its only chance for calm by assassinating Gaza military chief Ahem Jabari a day earlier.

Gershon Baskin, the founder and former co-director of the Israel/Palestine Center for Research and Information, told the Times of Israel that Jabari was just hours from giving his okay to a long-term ceasefire with Israel when a car he was riding in was blown up by Israeli forces, marking the start of Operation Pillar of Defense.

“This is complete and total insanity,” said Baskin, who has been in continuous contact with senior members of Hamas — although never directly with Jabari — over the past six years. “We are on the road to reoccupying Gaza.”

Baskin, who says he played a key role in negotiating for the release of kidnapped Israeli soldier Gilad Shalit last year, said Jabari would not meet with him, despite several requests during the Shalit talks.

“Jabari would never have direct contact with an Israeli,” Baskin said, noting that he communicated with Jabari through Hamas official and spokesman Ghazi Hamad.

“Jabari was interested in a long-term ceasefire; he was not interested in these repeated rounds of attacks with Israel,” Baskin said, based on recent conversations with Hamas and Egyptian security officials who were in direct contact with him. “Hamas knows that this whole cycle is futile. Hamas was dragged into the last rounds of violence because they were being accused of sitting on the side while Israel was killing their people.”

Speaking to the Times of Israel, Palestinian security officials in the West Bank affirmed that Jabari was indeed more moderate than other Hamas leaders in Gaza and believed in the necessity of a ceasefire with Israel.

Baskin’s engagement with Hamas began some six years ago, when he met a Hamas official at a conference in Cairo. The two tried to create a “discrete dialogue” between Israel and Hamas. Following a visit to Gaza’s Islamic University and meetings with Hamas officials there, Baskin even succeeded in attaining international funding for the move from four different countries. But the initiative was vetoed by the Hamas leadership.

Six days after the kidnapping of Shalit, Baskin was contacted by his Hamas interlocutor who proposed re-opening the channel of communication. Two and a half months later, Baskin says, that dialogue produced the first hand-written letter from Gilad Shalit proving that he was alive. The letter also proved the existence of an indirect channel of communication between Baskin and Shalit’s captor, Jabari.

For the past year Baskin has been trying to promote a proposal for a sustained ceasefire between Israel and Hamas. The proposal includes a mechanism for sharing intelligence information; an agreed definition for ceasefire breeches; and the installment of a hotline for crisis situations.

Both Hamas and Israel discussed the paper, Baskin says, but officially “decided not to decide.” On Monday, Baskin returned from Cairo where he discussed the initiative with Egyptian intelligence officials and his Hamas interlocutor.

He says that “the highest levels of Israel’s leadership” were aware of his mediation efforts, but to his great dismay “decided not to take that path.”

Israel’s attack on Gaza has not only broken the fragile calm brokered by Egypt’s General Intelligence Agency on the eve of Jabari’s assassination, Baskin argues, but the relationship with Egypt’s intelligence itself.

“I spoke to the key person in the Egyptian General Intelligence Agency immediately after I heard about the assassination,” Baskin said. “He was furious and frustrated and confused. He sees this is a direct slap in the face, and he is probably responsible for saving more lives in Israel and in Gaza than anyone else in this region.”