BISSAU (Reuters) - Guinea-Bissau's President Umaro Sissoco Embalo has dismissed Prime Minister Geraldo Martins just a week after his reappointment, according to a presidential decree issued on Wednesday, as the country navigates a political crisis.

       Embalo dissolved Guinea-Bissau's parliament days after what he said was a foiled coup on Dec. 1, accusing the government of passivity in response to the clashes. He then reappointed Martins as prime minister on Dec. 12.

       The decree did not provide a reason for sacking Martins, who is a member of the former ruling PAIGC party which now leads the main opposition coalition. Sources close to the matter said the prime minister and the president were at odds.

       The West African nation has often been in political turmoil and seen several coups since it gained independence from Portugal in 1974.

       Police fired tear gas last week to disperse opposition members of parliament who had tried to convene in defiance of Embalo's decision to dissolve the house. A date for new legislative elections has not yet been set.

       (Reporting by Alberto Dabo; Writing by Sofia Christensen; Editing by Nellie Peyton and Alison Williams)