Many Palestinians have expressed frustration with their leaders after sparring speeches from Mahmoud Abbas, the Palestinian president, and Khaled Meshaal, the leader of Hamas.
The two factions were poised to sign a national unity deal, paving the way for elections next June.
But Meshaal said on Sunday that "the timing is not right" and he criticised Abbas for his handling of a UN report on alleged Israeli war crimes in Gaza, while Abbas accused Hamas of exploiting the controversy over the report to obstruct unity.
Binyamin Netanyahu, Israel's prime minister, has also spoken out on the UN report, telling the Israeli parliament on Monday that it was one-sided.
Nour Odeh reports.
Source: Al Jazeera