The UN General Assembly has formally recognised Alassane Ouattara as the winner of Ivory Coast's disputed presidential election. The move came ahead of a meeting of West African heads of state to urge President Laurent Gbagbo to step aside. Earlier, the region's central bank handed over control of Ivory Coast's accounts to Mr Ouattara. Correspondents say the moves are increasing the isolation of Mr Gbagbo, who has insisted that he won the vote. The decision of the Central Bank of West African States could make it difficult for the incumbent president to pay the army. Violence since disputed election in November has left 173 people dead in Ivory Coast. A senior UN official said its investigators had also found evidence of extrajudicial executions, more than 90 cases of torture and 500 arrests, as well as abductions, kidnappings, acts of sexual violence, and destruction of property. The 28 November poll was meant to unite the country after a civil war in 2002 split the world's largest cocoa producer in two. The country's electoral commission ruled that Mr Ouattara had won, but the Constitutional Council said Mr Gbagbo had been elected, citing vote-rigging in some northern areas. The UN, which has about 10,000 peacekeepers in the country overseeing the peace process, has backed Mr Ouattara as the winner. He was given a further boost on Thursday when the General Assembly unanimously decided to recognise his choice of diplomats as the sole official representatives of Ivory Coast to the UN. Power-sharing ruled out The West African heads of state are scheduled to meet later on Friday in the Nigerian capital Abuja. The 15-nation the Economic Community of West African States (Ecowas) has already suspended Ivory Coast over Mr Gbagbo's refusal to hand over power. "It's a one-item agenda, and that's Cote D'Ivoire [Ivory Coast]," Sunny Ugoh, spokesperson for the regional body, told the BBC's Network Africa programme. "I believe that what we have done so far has put them under pressure, but I think perhaps we need to work a lot harder to increase the pressure to make sure that there's a transition to President Ouattara," he said. The BBC's Tomi Oladipo in Nigeria says there have been suggestions that member nations send in troops, to strengthen the presence of the international peacekeeping force. Nigeria, in particular, sent peacekeeping forces to Liberia and Sierra Leone during their civil wars in the 1990s, and is expected to do the same in Ivory Coast if the situation escalates, our reporter says. Nigerian President Goodluck Jonathan, who is also Ecowas chairman, has ruled out the possibility of accepting power-sharing government. In Ivory Coast Mr Ouattara and his supporters are currently holed up in the Golf Hotel in Abidjan, protected by 800 UN peacekeepers. They are in turn being blockaded by soldiers loyal to Mr Gbagbo. "There are three levers - diplomacy, finance and the army. Now there's only the third lever to get, and that will certainly be discussed today by Ecowas," Mr Ouattara's spokesman Patrick Achi is quoted by AFP news agency as saying. Mr Gbagbo still has control of state television and the public support of the army. The BBC's John James in Abidjan says without access to Ivory Coast's state accounts it is going to be extremely difficult to pay the salaries of soldiers and civil servants next month, even if Mr Gbagbo almost certainly has other financial reserves. The incumbent president has demanded that UN and French troops leave the country immediately. A close ally even warned that they could be treated as rebels if they did not obey the instruction. A US government specialist on Africa, William Fitzgerald, told the BBC that various options for defusing the crisis were being considered, but that "we're really trying to avoid violence if at all possible". Source: BBC