Palestinian reconciliation talks due to be held in Cairo were called off on Saturday after Hamas announced a boycott in protest at the detention of hundreds of its members by president Mahmud Abbas's security forces.
"They've been cancelled," Egyptian foreign ministry spokesman Hossam Zaki told AFP. Another Egyptian official, who asked not to be named, said the talks "have been delayed to an undetermined date... at the request of Hamas."
Hamas spokesman Fawzi Barhoum told AFP that "Hamas decided not to attend the dialogue talks in Egypt. We have informed the Egyptian authorities of our decision."
"Our decision was made because president Mahmud Abbas is continuing to weaken the Hamas movement and he has not released any Hamas detainees in the West Bank," he said.
Hamas and Abbas's secular Fatah movement have been bitterly divided since Hamas violently seized power in Gaza in June 2007, confining Abbas's rule to the Israeli-occupied West Bank and cleaving Palestinians into two hostile camps.
Abbas spokesman Nabil Abu Rudeina criticized Hamas's decision and blamed the group for being responsible for the failure of the talks.
"Hamas carries the responsibility for the failure of the Cairo dialogue and the responsibility for losing the opportunity to regain Palestinian unity and stop the division between Palestinians," he told AFP.
Abu Rudeina also denied Abbas has arrested Hamas members.
Abbas insisted his law enforcement forces arrested people who posed a security risk, irrespective of political affiliation. "They are arrested and brought to justice," he said at a joint news conference on Friday with U.S. Secretary of State Condoleezza Rice in the West Bank city of Ramallah.
Hamas expressed reservations about the plan, which calls for a politically independent transitional government to pave the way for new elections, saying Abbas would get an automatic extension of a term the Islamists insist ends in January.