JAKARTA (Reuters) - Indonesia's president removed Arcandra Tahar as energy and mining minister after less than a month on the job, the state secretary said on Monday, following reports that he held both Indonesian and U.S. citizenship.

Luhut Pandjaitan will serve as interim energy minister, while also maintaining his current position as coordinating maritime minister.

"To address public questions about the citizenship of Arcandra Tahar..., the president has decided to honorably remove Arcandra Tahar," State Secretary Pratikno told reporters.

Indonesia, the world's most populous Muslim-majority nation, does not recognize dual citizenship for adults.

Tahar, the former executive at Texas-based offshore engineering firm Petroneering, was part of President Joko Widodo's second cabinet reshuffle last month.

His removal after less than three weeks as minister is an embarrassment, analysts said.

"It's an embarrassing failure on the part of the government to conduct even the most basic due diligence," said Keith Loveard, Jakarta-based analyst with Concord Consulting.

(Reporting by the Jakarta bureau; Writing by Randy Fabi; editing by Mark Heinrich)