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AMMAN, May 29 (Reuters) - Jordan's King Abdullah appointed veteran politician Hani Mulqi as prime minister after dissolving parliament by royal decree on Sunday, following the end of its four-year term, and charged him with conducting new elections by October.

The monarch accepted the resignation of Prime Minister Abdullah Ensour, as is customary under the constitution, before appointing an interim head of government.

Under the constitutional rules the election should be held within four months under the constitution and after the lower house passed an amendment to the electoral laws in March government sources and political analysts say there are likely to be more candidates from political parties vying for votes with traditional tribal and family allegiances.

But Jordan's main political opposition to the government comes from the Muslim Brotherhood movement which is facing increasing legal curbs on its activities, leaving mostly pro-monarchy parties and some independent Islamists and politicians to compete in the elections, the sources say.

In 2011, under pressure from the popular protests across the Arab world, Jordan's parliament endorsed constitutional changes that devolved some of the monarch's powers to the parliament.

However, political analysts say tribal lawmakers who dominated the last parliament resisted any change which they saw undermining their influence and maintained a system that favours sparsely populated tribal regions which benefit most from state patronage and the support of the monarchy.

(Reporting by Suleiman al-Khalidi; Editing by David Goodman and Greg Mahlich) ((suleiman.al-khalidi@thomsonreuters.com; +962 79 5521407; Reuters Messaging: suleiman.al-khalidi.reuters.com@thomsonreuters.net))