In an interview Monday with Italy's RAI TV, Abbas charged that "thanks to the support of Hamas, Al Qaeda is entering Gaza."
Hamas spokesman Sami Abu Zuhri accused Abbas of trying to whip up sentiment against Hamas, which vanquished the president's forces in Gaza last month and unseated his political party in 2006 parliamentary elections.
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"Hamas has no link to Al Qaeda," Abu Zuhri said. Abbas "is trying to mislead international opinion to win support for his demand to deploy international forces in Gaza."
Abbas, who is to meet with Italian Prime Minister Romano Prodi in the West Bank town of Ramallah on Tuesday, offered no evidence to back up his allegations.
Al Qaeda's presence in the Palestinian territories has been a subject of intense speculation since the 2001 terror attacks on New York and Washington.
Al Qaeda's second-in-command, Ayman al-Zawahri, recently issued a call for supporting Hamas. But Hamas leaders, fearful of deepening the group's international isolation, have suggested they would steer clear of Al Qaeda, in line with the movement's long-standing position to stay focused on the conflict with Israel.
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