Nabil Abu Rdainah, an adviser to the Palestinian president, said Mahmoud Abbas's first decree since the new government government was formed re-established a Palestinian National Security Council that will, in theory, oversee all of the security services.
"All issues will be presented before the security council in order to determine solutions," Abu Rdainah said.
The decree also appointed Mohammad Dahlan, a powerful Fatah leader who led a crackdown on Hamas in the 1990s, as national security adviser.
In recent months, Hamas activists have accused Dahlan of trying to assassinate Haniya and of unofficially commanding pro-Fatah forces in the factional fighting.
"We are ready to forget the past, but we will be looking to the future and everybody is going to face the test," Fawzi Barhoum, a Hamas spokesman, said of Dahlan.
Israel has refused to talk to the coalition, saying it fails to meet international demands - renouncing violence, recognising Israel and honouring past peace deals.
"This is just a ploy to regain international hand-outs with smoke and mirrors"
LeotheIsaurian, Detroit, US
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Ehud Olmert, the Israeli prime minister, on Sunday called on the international community to join Israel in shunning the new government, saying: "The platform of the new government includes very problematic elements."
He told the Israeli cabinet that he will not work with the new body, but would maintain contact with Mahmoud Abbas, the Palestinian president and leader of Fatah.
The cabinet endorsed Olmert's position by 19 votes to two, Israeli radio stations reported.
Norway announced on Saturday that it would now recognise the incoming government.
Jonas Gahr Stoere, the Norwegian foreign minister, said he was satisfied the unity government had taken sufficient steps towards meeting international demands.
Russia and France have also indicated a willingness to work with the Fatah-Hamas coalition.
Arab countries including Syria, Jordan, Qatar and Yemen have called for the aid boycott to end.
|Mohammad Dahlan, right, led a crackdown |
on Hamas fighters during the 1990s [EPA]
However, Israel has called on the Quartet group - the US, EU, UN and Russia - to maintain its sanctions, which were imposed on the Palestinian Authority one year ago after the election of a Hamas government.
The US said it was "disturbed" by Haniya's reiteration of the Palestinian right to resist Israeli occupation during his speech before the parliamentary vote on the government.
"The national unity government's platform reference to the right of resistance is disturbing and contradicts the Quartet principles of renunciation of violence," Nancy Beck, a US state department spokeswoman, said.
Ziyad Abu Amr, the new foreign minister, said: "The Israeli government is weak and is running away from negotiations by clinging to old irrational positions."
He urged Israel to co-operate with the new government, saying there was a new opportunity to establish co-operative ties. Speaking to Israel Radio, he dismissed the calls for formal recognition of Israel as "semantics".
Ahead of the first cabinet meeting on Sunday the new ministers were in optimistic mood.
"Its the first national unity government in the history of the Palestinian people," Mustapha Barghouti, information minister, told Al Jazeera.
"It means consolidating the democratic system in Palestine it means ending any form of internal violence, and it means consolidating the Palestinian efforts to achieve freedom, independence and the end of occupation."
Ministers in the West Bank had to take part in the meeting by video link because of Israeli restrictions on travel between the Palestinian territories.
On the streets of Gaza City, the unity government was welcomed.
Sadi Shurab, 36, said: "We hope this government ... ends the chaos and the economic boycott.
"We hope it returns salaries to the government employees and provides work for the unemployed."
Abd al-Wahab Salim said: "I am happy with the announcement of the unity government, but I don't feel like partying ... I want a life of dignity without fear."