By Yasmine Saleh
CAIRO (Reuters) - A Muslim Brotherhood leader vowed on Friday that members who join other political parties would be expelled from the group, in the latest sign of internal rifts.
The Brotherhood, Egypt's biggest political group, is seen as the best prepared for a parliamentary vote due in September. But divisions have emerged over electoral strategy.
The Brotherhood's secretary-general, Mahmoud Hussein, was quoted on Friday by al-Shorouk newspaper as saying members who join other political parties would be forced to leave the group.
"They either voluntarily resign from the Brotherhood or they will get fired," Hussein was quoted as saying.
Last week, the Brotherhood expelled Abdel Moneim Abul Futuh, a senior member who had announced he would run as an independent in a presidential vote later this year, defying a Brotherhood decision not to field a candidate for the post vacant since President Hosni Mubarak's overthrow in February.
Hussein said young Brotherhood members who were working with Abul Futuh in his presidential campaign would be investigated.
Political analyst Mustapha al-Sayyid said the Brotherhood, which has formed its own "independent" Freedom and Justice Party, wanted to exert internal discipline before the election.
"It wants to give public opinion the impression it is in full control over all its members," he said.
Abel Rahman Fares, spokesman of "Egyptian Current," a party being formed by Brotherhood members and others, said he did not understand the logic behind the Islamist group's position.
"Not all members of the Brotherhood are required to join the group's party," he said. "They should be allowed to join other parties if they want to."
Ibrahim el-Zafarany, who is founding the "Renaissance" party, which has some Brotherhood members, said the Islamist group should not mind if its supporters joined other parties.
"The Muslim Brotherhood has a very strong party in terms of finances and human resources. So it is not understood why it gets upset if some of its members who did not join its party decide to join other parties," Zafarany told Reuters.
The Brotherhood, officially banned but semi-tolerated under Mubarak, has said it will contest half of parliament's seats, seeking to capitalize on the grass roots networks it has nurtured during decades of medical, social and charity work.
The September election could be Egypt's first free vote after decades of widespread vote-rigging in favor of Mubarak's ruling party. It will also be seen as a test of the true strength of the Brotherhood and its political opponents.
(Editing by Alistair Lyon)