Interviewed on Israel Radio, Mr. Barak was asked about a classified report submitted to him on guidelines for handling negotiations regarding abducted soldiers. The interviewer asked whether the rules were expected to be made stricter so it would “no longer be 1,000 terrorists for one soldier.”

“I believe that will be the conclusion,” Mr. Barak said. “There is no choice. We have to change the rules fundamentally to protect the state’s overall interests.” He said an important part of the report’s conclusions were on “how to approach the negotiations, in what framework, with what rules, and I think it’s clear that the rules will be a lot stricter.”

The exchange was made for the freedom of Gilad Shalit, the Israeli sergeant who was captured by Hamas in a cross-border raid and held for more than five years in a case that wrenched Israelis.