The former US president Jimmy Carter today said Hamas was prepared to accept Israel's right to "live as a neighbour next door in peace".
Carter was speaking after meeting Khaled Meshal, an influential leader within the militant organisation, in Damascus last week.
The former president insisted Hamas would not undermine efforts by the Palestinian president, Mahmoud Abbas, to reach a peace deal with Israel.
Hamas believes any peace agreement negotiated by Abbas would have to be submitted to the Palestinian people in a referendum, he added.
"There's no doubt that both the Arab world and Hamas will accept Israel's right to exist in peace within 1967 borders," Carter said.
However, Sami Abu Zuhri, a Hamas spokesman, later said Carter's comments "do not mean that Hamas is going to accept the result of the referendum".
The US and Israel have criticised Carter's decision to meet officials from Hamas, which they consider to be a terrorist group.
The Israeli prime minister, Ehud Olmert, refused to meet him because of his insistence that Israel should talk to Hamas.
Carter said it was a "problem" that Israel and the US refused to engage with the militant group, adding that peace negotiations had "regressed" since a US-hosted conference in Annapolis in November.
"The problem is not that I met with Hamas in Syria," he said. "The problem is that Israel and the United States refuse to meet with someone who must be involved."
Carter - who won the Nobel peace prize in 2002 - also said Hamas had promised to allow a captured Israeli soldier to send a letter to his parents and "made clear to us that they would accept an interim ceasefire in the Gaza Strip".
However, he said Hamas had rejected his proposal for a month-long unilateral ceasefire.
He added that Syria wanted the US to play a "strong role" in facilitating renewed peace negotiations between Syria and Israel.