Dennis Ross said the United States should back a cease-fire in Gaza only if it ensures that Hamas "can't rebuild."

"We want some stability," said Ross, a former top Middle East negotiator in the Clinton administration, in a talk at Temple Beth Ami in Rockville, Md.

"If Hamas is left with the capability to rearm," he said, then the current conflict will have been "just a prelude" to the next round. He hoped that some sort of "enforcement mechanisms" to restrain the terrorist group could be developed in any kind of truce.

Ross, a counselor and distinguished fellow at the Washington Institute for Near East Policy, said achieving an Israeli-Palestinian agreement now would be much different than his last attempt in 2000. Not only is the Palestinian Authority divided and much weaker, he said, but the Israeli public doesn't believe such an agreement is possible.

Israel left Lebanon and Gaza, and in both instances, "things got a whole worse" -- which doesn't provide much confidence about a withdrawal from the West Bank, he said.

Ross' talk was part of a series of programs on Israel at the synagogue and planned before the current Gaza conflict broke out.