KUWAIT (Reuters) - Kuwait's ruler reappointed Sheikh Jaber al-Mubarak al-Sabah as prime minister after Saturday's election in the Gulf state and asked him to form a new cabinet, state news agency KUNA said on Monday.

Sheikh Jaber, who has held the post since late 2011, will now form a new government of around 15 ministers, with top posts expected to go to members of the ruling Al-Sabah family.

The sixth election since 2006 brought in a parliament seen as more willing to cooperate with the government than some of its predecessors, raising hopes that economic development projects will move forward in the major oil producer and U.S. ally.

Kuwait's emir, Sheikh Sabah al-Ahmad al-Sabah, on Sunday accepted the resignation of the outgoing prime minister, as is the norm following a new parliamentary election.

The outgoing cabinet, complying with Kuwait's laws, had approved a draft decree inviting new lawmakers to hold their first parliamentary session on August 6.

Kuwait has the most open political system in the Gulf Arab region but parliaments have been repeatedly dissolved over procedural disputes or for challenging the government.

(Reporting by Sami Aboudi; Editing by Mark Trevelyan; editing by Jon Hemming)