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AMMAN, Sept 28 (Reuters) - Jordan's King Abdullah has sworn in a new government headed by Hani Mulki as prime minister for a second term and with foreign, finance and economic ministerial posts kept unchanged, state media and officials said.

Mulki, 64, who has held a string of senior diplomatic and ministerial posts, was first appointed last May to oversee the parliamentary elections that were held last week.

He was reappointed last Sunday and tasked with reviving a sluggish economy and business sentiment hit by regional turmoil by overseeing a new International Monetary Fund-guided programme that started this year.

In Jordan's constitutional monarchy most powers rest with the king, who appoints governments, approves legislation and can dissolve parliament.

The key finance, foreign and finance ministerial posts would remain unchanged and the 29-member cabinet would as before be dominated by a mix of technocrats, conservative politicians and tribal loyalists.

Mulki will face a more assertive parliament when it convenes for the first time next month after Jordan's Muslim Brotherhood gained a foothold in last week's election.

The Islamist movement ended a decade-long boycott of mainstream politics and returns as the mainstay of a broad civic alliance.

Although the alliance is not large enough to block legislation or cabinet appointments, it should nevertheless allow for livelier debates in the assembly that could undermine public support for government policies.

Parliament has been so passive in recent years that successive governments have been able to enact draconian temporary laws restricting public freedoms.

(Reporting by Suleiman Al-Khalidi; Editing by Raissa Kasolowsky) ((suleiman.al-khalidi@thomsonreuters.com; +962 79 5521407; Reuters Messaging: suleiman.al-khalidi.reuters.com@thomsonreuters.net))