The US State Department said today it had advised former President Jimmy Carter against meeting the leader of Hamas in Syria next week, saying it went against US policy of isolating the militant group.
Mr Carter plans to visit Israel, the West Bank, Egypt, Syria, Saudi Arabia and Jordan during a nine-day trip due to start on Sunday but gave no details of specific meetings.
"This is a study mission and our purpose is not to negotiate but to support and provide momentum for current efforts to secure peace in the Middle East," the Carter Center said in a statement.
"Our delegation has considerable experience in the region, and we go there with an open mind and heart to listen and learn from all parties," it said.
Mr Carter, who won the Nobel Peace Prize in 2002, discussed with the State Department's point person on Israeli-Palestinian issues, David Welch, his plans to meet exiled Hamas leader Khaled Meshaal in Damascus, but the department said it went against US policy.
"We counseled against it," said State Department spokesman Sean McCormack.
"US government policy is that Hamas is a terrorist organization and we don't believe it is in the interests of our policy or in the interests of peace to have such a meeting."
Israel's ambassador to the United States, Sallai Meridor, also expressed concern over such a meeting. "The unintended consequences of such a meeting would be to embolden terrorists and undermine the cause of peace," he said.
Mr Carter (83) served one term as president from 1977 to 1981. He succeeded in negotiating the 1978 Camp David Accords that paved the way for peace between Israel and Egypt but he has increasingly taken positions highly critical of Israel.
In a 2006 book, he described Israeli policy in the occupied territories as "a system of apartheid."
US policy is to isolate Hamas, which has control of Gaza and is committed to the destruction of Israel. Washington sees pro-Western Palestinian President Mahmoud Abbas as its partner in US-sponsored peace talks with the Israelis.