"It was a declaration of a coup against the government," said Mushir Al Masri, a leading Hamas legislator, calling on Palestinians to boycott the vote.
"Whoever announced the referendum should shoulder the responsibility for the dangerous consequences that may result," Masri said.
Prime Minister Ismail Haniyah has announced that he would meet Abbas to express his rejection of the referendum.
"During this meeting with Abbas, I will discuss the dangers of this referendum," Haniya said, emphasising that he remained open to talks," he said.
"I say yes to dialogue, no to the referendum. Dialogue must be the lone path."
An emergency session of parliament will be convened on Monday to "discuss the legality of the
referendum".
Hamas' military wing has ended its ceasefire with Israel in response to the artillery attack that killed eight people on a Gaza beach.