Leader, Khaled Meshaal, told a rally in the Syrian capital of Damascus, "We will not enter a new truce while our people are surrounded and are preparing for a new round of conflict."
"We have had enough of the truce while our prisoners are still held," he told a meeting marking 38 years since the creation of the Popular Front for the Liberation of Palestine.
Palestinian groups agreed to the truce at a meeting in Cairo in March, but it has been far from water tight.
Since Monday's suicide attack, which was claimed by Islamic Jihad, dozens of activists from all the main armed factions have been arrested by Israeli troops in the West Bank.
Over 20 Hamas members were arrested Thursday, including the mayor of Beit Liqiya, a town near Ramallah in the West Bank.
The United States shrugged off news of the Hamas' decision.
"We've always made clear that truces are good only insofar as they go, and
that's really not very far," said deputy State Department spokesman Adam
Ereli.
He accused Hamas of pursuing violence against innocent civilians and urged
the Palestinian Authority to take action against it and another group, the
Palestinian Islamic Jihad.