<div><p>ABUJA (Reuters) - Nigeria's ailing president, in hospital overseas for the past two months, faced mounting pressure on Thursday to end a power vacuum that is increasingly worrying investors.</p><p>Critics want President Umaru Yar'adua to formally hand over executive powers to his deputy or quickly return to ease uncertainty in sub-Saharan Africa's second-biggest economy.</p><p>Thousands marched in Lagos to protest Yar'Adua's absence, while the Nigerian Bar Association urged a federal court in Abuja to intervene in the political crisis.</p><p>Yar'Adua has not been seen publicly since leaving Nigeria on November 23 to be treated for a heart ailment in Saudi Arabia.</p><p>The 58-year-old leader has refused to formally transfer power over to Vice President Goodluck Jonathan, prompting a federal court last week to rule that Jonathan can exercise executive powers but cannot be "acting president."</p><p>The uncertainty has slowed government business, threatens a fragile peace in the oil-producing Niger Delta and raises concern about the legality of decisions made while Yar'Adua is in hospital.</p><p>"In the president's absence, and realistically until a new president is elected in 2011, the outlook will deteriorate for foreign investors and security will decline in terms of regulatory risk and political violence," said Elizabeth Stephen, an analyst with London-based insurance broker Jardine Lloyd Thompson.</p><p>Despite the constitutional risks, some investors are hoping the vice president will take charge so that reforms, especially in oil and the banking sectors, can get back on track.</p><p>"The markets would be at ease if the vice president showed initiative on the petroleum industry bill or other reforms that would enhance his administration's credibility," said Bismark Rewane, head of Lagos-based consultancy Financial Derivatives.</p><p>Jonathan made his first use of executive powers to send troops into the city of Jos earlier this week to quell bloody sectarian riots.</p><p>But the move was viewed by analysts more as a response by the to a humanitarian crisis than as a step by the vice president toward assuming greater influence.</p><p>The clashes in Jos are in any case not seen as immediately affecting the investment outlook for Nigeria.</p><p>A government official told Reuters on Wednesday the vice president would continue performing executive powers, including signing bills if necessary, while Yar'Adua was overseas.</p><p>THOUSANDS PROTEST</p><p>Chanting "Yar'Adua where are you?" and holding signs saying "Enough with the offshore president", more than 3,000 Nigerians marched to the state government headquarters in Lagos demanding Yar'Adua give up his executive powers or return to Nigeria immediately.</p><p>"With Yar'Adua, nothing has changed. He should go and let people who are able to lead, lead the country," said pastor Tunde Bakari, who was surrounded by dozens of people with "Enough is enough" emblazoned on their white T-shirts.</p><p>This is the second major street protest against Yar'Adua in the last 10 days. On Wednesday, a group of senior Nigerian figures petitioned parliament to resolve the problem of Yar'Adua's absence.</p><p>In Abuja, a federal court heard a lawsuit from the Nigerian Bar Association (NBA) against the government which accuses the president of breaching the constitution by remaining in power.</p><p>Under the constitution, Yar'Adua must write a letter to the heads of both houses of parliament requesting his presidential duties be temporarily handed over to the vice president in his absence.</p><p>"It is not discretionary on the president to give the letter. It is mandatory," said the NBA's lawyer, Akin Olujimi.</p><p>But the government disagreed and said the judiciary does not have the right to get involved in the succession of the presidency.</p><p>"The court does not have the power to make the vice president the acting president," said Attorney General Michael Aondoakaa.</p><p>The court case has been adjourned until January 29.</p><p>(Additional reporting by Hannington Osodo in Lagos and Peter Apps in London; Writing by Randy Fabi; Editing by Giles Elgood)</p><img src="http://admatch-syndication.mochila.com/images/ad.gif?aid=67436304&bid=informcom" /></div><div id="copyright"><div>

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