A senior official in the Palestinian Fatah faction said security services for the rival Hamas group are nothing more than "armed militias."
It's not clear what prompted Azzam el-Ahmed's harsh comment but it suggested the factions are no closer to reconciliation.
Repeated efforts to reconcile the sides have failed. The factions have been bitterly divided since militant Hamas seized Gaza in 2007, leaving Fatah only in control of the West Bank.
The main sticking points between them are the merging of their security forces and hammering out a joint political program, including peace with Israel.
El-Ahmed spoke to The Associated Press on Tuesday, ahead of a new round of reconciliation talks between the two Palestinian sides this week in Damascus.
Last week, Hamas official Izzat al-Rishq said the talks on security cooperation with Fatah could narrow Palestinian divisions but suggested that reconciliation was some way off, citing disagreement over the Palestinian Authority's peace negotiations with Israel.
Rishq said that the PA's recent peace talks with Israel had divided the Palestinian people.
The direct talks between Israel and the PA have been on hold since a 10-month partial Israeli freeze on settlement building in the West Bank expired on September 26.
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