Palestinian President Mahmoud Abbas on Saturday called off a meeting with the head of the Hamas-led government, signaling a new snag in power-sharing talks between the sides.

Abbas and Prime Minister Ismail Haniyeh of Hamas had been expected to meet late Saturday. Earlier in the day, officials from both sides had expressed optimism that a deal would be reached.

Officials from Abbas' Fatah party said he called off the meeting because he wasn't comfortable with Hamas' position on certain key issues.

The officials, who spoke on condition of anonymity because they weren't authorized to speak to the media, said Abbas wants all remaining areas of disagreement resolved before he holds the meeting with Haniyeh. Abbas is expected to be in Gaza until Tuesday before returning to his West Bank headquarters.

Abbas has been pressuring Hamas to accept a proposal that implicitly recognizes Israel or face a July 26 referendum on the matter.

Abbas has endorsed the plan as a way to end weeks of infighting and lift an international boycott against Hamas. Hamas, sworn to Israel's destruction, has refused to accept the deal.