Nigerian Foreign Minister Ngozi Okonjo-Iweala has resigned only days after being replaced as head of the country's economic reform team, the government reported on Thursday.

Nigerian President Olusegun Obasanjo reassigned the former World Bank executive from the Finance Ministry to Foreign Affairs in June without any prior notice. Mrs. Okonjo-Iweala had remained head of the economics team, but this week was replaced by the new Finance Minister, Nenadi Usman.

A government statement cited the president as accepting Mrs. Okonjo-Iweala's resignation based on your compelling need to take care of pressing family issues.

Mrs. Okonjo-Iweala was assigned by President Obasanjo as Finance Minister in 2003 to reform the country's collapsed finances. She went on to negotiate Africa's biggest ever cancellation debt of $30 billion to the Paris Club which saved the country $18 billion.

With Nigeria's status as a top oil producer, Okonjo-Iweala also took the opportunity to save the oil export profits as part of her reforms to lift the country's economy. She is popular with foreign investors who approve of her cautious macro-economic management policy.

Her successor, Nenadi Usman has agreed to keep the current reform program following the positive results it has brought to Africa's most populous country.