Hamas sources said last week the group had accepted a U.S.-backed deal, but on Thursday political bureau member Bassem Naim said the new version meant "the continuation of killing and famine... and does not meet any of our people's demands, foremost among them halting the war."
"Nonetheless, the movement's leadership is studying the response to the proposal with full national responsibility," he added.
A source close to the group said the new version "is considered a retreat" from the previous one, which "included an American commitment regarding permanent ceasefire negotiations."
According to two sources close to the negotiations, the new proposal involves a 60-day truce, potentially extendable to 70 days, and the release of five living hostages and nine bodies in exchange for Palestinian prisoners during the first week.