"If they want to meet then we will meet them, in accordance with their request," a Hamas offical told the Reuters news agency.
Zeid said the delegation would hold talks with Fatah members and other representatives from allied factions within the Palestine Liberation Organisation (PLO).
The discussions will centre on recent efforts by Abbas to hold reconciliation talks with Hamas.
"We should focus our efforts on implementing the initiative in order to reach out for national unity to confront the dangers threatening the Palestinian cause," Zeid said, referring to a Hamas-Fatah mediation drive by Ali Abdallah Saleh, the Yemeni president, that has been stalled for months.
Abbas called for reconciliation talks earlier this month, although he previously insisted that Hamas give up control of Gaza before dialogue could begin.
Officials from the two factions met in the West African country of Senegal later.
Those talks restored "an atmosphere of trust and mutual respect", a joint Hamas-Fatah statement said.All-faction meeting
Zeid said Arab peace brokers were trying to organise a meeting of all Palestinian factions in Cairo by the end of the month.
Marwan Abdel-Hamid, a Fatah delegate, said his faction preferred to meet Hamas along with other groups and not "bilaterally".
Ismail Haniya, the Hamas leader in Gaza, last week voiced a preference for direct talks with Fatah.
The two main Palestinian factions have been bitterly divided since Hamas seized power in the Gaza Strip a year ago, after ending more than 40 years of Fatah's unchallenged leadership of the Palestinian people with a victory in a parliamentary election in 2006.
Hamas fighters went on to rout Fatah forces and take over the Gaza Strip in June 2007.