Akhir 27, 1432 / April 1, 2011, SPA -- U.N. Secretary-General Ban Ki-moon on Thursday called for all combatants in the Ivory Coast to show "maximum restraint" amid reports of heavy fighting in the commercial capital Abidjan. Ban also said that incumbent leader Laurent Gbagbo should immediately cede power to his rival Alassane Ouattara to "enable the full transition of state institutions to the legitimate authorities." A statement from Ban's press office said he "urges all parties to abide by their responsibility to avoid harm to the civilian population." "The secretary-general urges all to exercise maximum restraint, refrain from exacting revenge and place the interests of the whole nation above all else," the statement said. Forces loyal to Alassane Ouatara, the internationally recognized winner of the Nov. 2010 poll, are reported to have reached Abidjan on Thursday. The U.N. mission in Cote d'Ivoire also reported that a siege by Gbagbo forces of the Golf Hotel in Abidjan had been lifted. The hotel has been the headquarters of Ouattara and his government since the elections and was under U.N. protection. The U.N. has some 12,000 peacekeepers in the Ivory Coast and the Security Council has urged them to act strongly in carrying out their mandate, including protecting civilians. The peacekeepers are there as part of a 2004 peace agreement that ended a civil war. On Wednesday, the council imposed a travel ban and assets freeze of Gbagbo and his inner circle.