Nigerian President Umaru Yar'Adua unveiled his new cabinet Thursday, nearly two months after he became leader of Africa's most populous country.  The cabinet includes some opposition elements in what is labeled a government of national unity. For VOA, Gilbert da Costa in Abuja reports.

President Umaru Yar'Adua's ruling Peoples Democratic Party came to power in April elections that were marred by violence and alleged vote rigging and were deemed largely flawed by local and international observers.

In naming his cabinet, the president brought some of his critics into the new government.

The main opposition party, the All Nigeria Peoples Party, was given two ministerial slots for agreeing to join the government of national unity.

But President Yar'Adua retained the vital oil portfolio, while veteran politician and ruling party official, Ojo Maduekwe, is the new foreign minister.

Action Congress, Nigeria's second largest opposition party rejected an offer to be part of the new administration.  Party spokesman Lai Mohammed explains.

"The presidential system of government that we operate today makes no provision for a government of national unity," he said.  "We also believe that joining the government of national unity will negate all that we've stood for throughout all the years, which is multi-party democracy."

Representatives from each of Nigeria's 36 states are included in the 39-member cabinet as stipulated by Nigerian law. Government appointments in Nigeria follow a very complex and cumbersome process that seeks to accommodate Nigeria's ethnic and religious diversity.

However, University of Abuja political scientist Hameed Ojo says the result of the complex system is appointments that are not always based on merit.

"We are operating a federal system of government which is not like the American system," he explained.  "Whereas in the United States of America, the president appoints his ministers and these ministers are directly responsible to him, here, theoretically it is the same, but so many factors are at work. We have what is called federal character. The various states have to be represented, the various zones must be represented, and of course, you have special interests. So, what actually determines appointment here is not merit."

Mr. Yar'Adua was sworn in as president of Nigeria, Africa's leading oil exporter, in May, which marked the first transfer of power from one civilian administration to another in Nigeria since its independence from Britain in 1960.