By Felix Onuah and Camillus Eboh
ABUJA (Reuters) - Nigerian Vice President Goodluck Jonathan assumed office as acting president on Tuesday to fill a power vacuum more than two months after President Umaru Yar'Adua left for medical treatment in Saudi Arabia.
Parliament earlier recognised Jonathan as acting head of state in an effort to end uncertainty that has threatened to paralyse government business in Africa's most populous nation and reignite violence in the main oil region.
"The circumstances in which I find myself assuming office today as acting president of our country are uncommon, sober and reflective," Jonathan said in an address on national television, urging Nigerians to pray for Yar'Adua's recovery and return.
The fact that there was no formal transfer of power had led to doubts over who was ruling the country and raised the prospect of the worst political crisis since the end of military rule more than a decade ago.
But any shift in control is deeply sensitive in a country of 140 million split between Yar'Adua's Muslim north and Jonathan's largely Christian south, scores of ethnic groups and myriad other factions seeking a share of state resources.
A sombre Jonathan addressed Nigerians in the broad brimmed hat favoured by chiefs from his oil producing Niger delta region. In reality, he had already taken on much of the president's role, including deploying troops to quell unrest.
Although Nigeria's cabinet has previously opposed any formal transfer of powers, the justice minister said Jonathan had the government's full support -- suggesting it would not obstruct him from acting as president.
"What is important now at this stage is to move the country forward," said Justice Minister and Attorney General Michael Aondoakaa.
Motions backed earlier by both chambers of parliament enable Jonathan to pass legislation and act as commander of the armed forces until Yar'Adua declares he is fit enough to resume work.
"What they have done is good. It's not good for the country to be without a president. Everything was lying undone," said Stephen Olahilehin, an ex soldier and policeman.
"Now Goodluck can continue until Yar'Adua comes back alive or dead," he added.
RETURN UNLIKELY
"All signs are there is no way Yar'Adua will come back," said Antony Goldman, head of London-based PM Consulting.
"Although this removes some of the uncertainty, there is still uncertainty over what is going to happen ... The problem with Nigeria was never that Yar'Adua was sick, it is the weakness of the institutions."
Nigerian politicians are already turning to the campaign for elections due by 2011 and the fact that Yar'Adua now appears extremely unlikely to contest a second term will only intensify the battle.
Both the Senate and House of Representatives made clear that Jonathan would hold executive powers only until the president could resume office.
But the opposition Action Congress, which wants Yar'Adua removed completely, dismissed the motions by parliament and Jonathan's announcement.
"It is an illegality and an exercise in futility. It is unconstitutional," said spokesman Lai Mohammed, suggesting that Jonathan's legitimacy would be open to legal challenges.
Despite the constitutional doubts, Jonathan's empowerment means that government business can go on and that he will be able to sign the 2010 budget into law once it is agreed in parliament.
"This is a move in the right direction. We are moving closer to closure," said Bismarck Rewane, chief executive of Lagos-based consultancy Financial Derivatives.
Jonathan said the government would take every step necessary to build on the gains of an amnesty programme in the oil-producing Niger Delta. Militants in the region have threatened fresh attacks, saying Yar'Adua's absence was slowing the programme.
