The two top leaders of the Islamist Palestinian group Hamas met at secret talks in Qatar on Sunday to resolve an internal crisis over a reconciliation pact with the Fatah movement of President Mahmoud Abbas, a diplomat in the region said.

The first open leadership split in the 25-year history of Hamas arose over how far it should go in closing ranks with Fatah.

"Khaled Meshaal and Ismail Haniyeh met last night in Qatar to discuss the dispute in Hamas over the Doha agreement," the diplomat told Reuters on Monday, naming the two main figures in the organisation.

Meshaal has recently quit his longtime Damascus headquarters, politically embarrassed by Syrian President Bashar al-Assad's bloody crackdown on an uprising waged by fellow Sunni Muslims. Haniyeh flew to Qatar from Iran.

The two Islamist leaders are not, however, on opposing sides of the internal dispute in Hamas, but are trying to resolve differences in its collegial leadership between Meshaal and Gaza-based group leaders close to Haniyeh, analysts say.

"The crisis persists," the diplomat told Reuters after the Qatar meeting. He asked not to be identified.

Hamas and Fatah have been saying for over a year that it is high time to end their damaging rivalry.

"Dispute"

Some in the top ranks of Hamas believe that with Middle East peace talks now on the rocks, the recent rise of Islamist movements in the Arab world gives them more leverage over Western-backed Abbas than they have ever had.

But Hamas leader-in-exile Meshaal, with close ties to Egypt's Muslim Brotherhood, sees it as a time for accommodation rather than confrontation, together with subtle policy adjustments to end Hamas's isolation.

Meshaal and Abbas signed a pact in the Gulf state of Qatar last week, according to which Abbas would lead an interim government of technocrats with the task of preparing for overdue presidential and parliamentary elections later this year.

Haniyeh, the Hamas leader in Gaza, backed the deal but other senior Hamas figures in Gaza were vocally opposed, pitching the movement into a rare open dispute.

Haniyeh flew to Qatar from Iran, where he met leaders of the Islamist Republic. Relations have soured in past year over the lack of public support from Hamas for their common ally Assad in his handling of Syria's uprising.

A statement from Haniyeh said Iran reaffirmed its support for the Palestinian people "and by all means to reinforce the steadfastness and resistance against the (Israeli) occupation."

Diplomats say Iran aid has been suspended since August 2011.

"Mistake"

The Qatar deal, which would make Abbas president and prime minister at the same time for the duration of the interim government, angered those in Gaza who feel Meshaal made too big a concession to the Palestinian leader in the Israeli-occupied West Bank without obtaining their approval.

Under Hamas rule, Gaza effectively runs its own affairs.

Meshaal has until recently been based in the Syrian capital, Damascus, but is now seeking new headquarters.

Haniyeh is top man in Israeli-blockaded Gaza, heading a more disparate group of senior figures with divergent views.

The Hamas-Fatah pact aims to heal five years of political division since Hamas seized control of Gaza and ejected Fatah from the enclave. Te Palestinians remain split politically, on top of geographically.

Mahmoud Al-Zahar, a senior Hamas figure in Gaza, described Meshaal's agreement with Abbas as a "mistake". Zahar clashed with Meshaal late last year when the exiled leader advocated giving Abbas more time to pursue his peacemaking with Israel.

Hamas sources say some officials are demanding that the group should have key portfolios in the proposed interim government if Abbas is to be prime minister as well as president. That would violate the whole point of the interim arrangement, which is that the government must be made up of political independents, not men from factions.