ABIDJAN (Reuters) - Many workers in Ivory Coasts main city Abidjan ignored a call by presidential claimant Alassane Ouattara for a strike on Monday to force Laurent Gbagbo out of power, saying they must work in order to eat. Operations at the ports of Abidjan and San Pedro, through which much of Ivory Coasts cocoa exports are shipped, were normal on Monday morning. Abidjans downtown Plateaux business district was bustling, with shops and offices open. In the rebel-controlled northern city of Bouake, a bastion of support for Ouattara, some shop owners heeded the strike though banks and public transport were functioning. Meanwhile, supporters of Alassane Ouattara said they had occupied the Ivorian embassy in Paris on Monday, calling for the internationally isolated incumbent Laurent Gbagbo to step aside. French television reported that around 15 people had managed to enter the building and the embassy staff had peacefully left. A police spokesman had no immediate comment. The turmoil has sent cocoa futures to four-month highs, while the countrys Eurobond has dipped to a record low on concern that the government will miss a $30 million bond payment on December 31. However, cocoa exporters said volumes of cocoa arriving at ports had exceeded levels last year despite the crisis. Ivorians live on a day-to-day basis. To ask us not to work is to ask on not to eat. For civil servants it might not be a problem, but for us ... it is a real problem, said Ebrotie Assomou Jean, a trader in Abidjans Cocody district. International pressure has piled on Gbagbo to step down since the November 28 election, though he has shown no sign of caving and insists he won after the nations top court- run by one of his allies - threw out hundreds of thousands of Ouattara votes citing fraud.. A similar call for civil disobedience last week by Ouattaras rival government was not largely followed. But at least 20 people died when Ouattara supporters tried to seize the state broadcaster RTI as they stopped by government soldiers. We are observing the situation. We are half-open. We will wait until midday to see, if everyone is not on strike, then we will continue work as normal, said Emile Ngoran who sells appliances in Bouake. Road traffic in Abidjan was also normal the day before a visit by three west African heads of state, sent by ECOWAS to urge Gbagbo to quit. ECOWAS has threatened to use force if he does not relinquish power. The African Union on Monday backed the regional effort and the mission of the three heads of state to end the crisis. It said in a statement it had asked Kenyan Prime Minister Raila Odinga to follow through the situation. In an interview with Frances Le Figaro newspaper on Sunday, Gbagbo said he was not worried by the ECOWAS threat to remove him by force. All threats must be taken seriously. But it would be the first time that African countries were willing to go to war against another country because an election went wrong, Gbagbo said. He also said he was a victim of an international plot by France and the United States. French foreign ministry spokesman Bernard Valero dismissed the accusations as baseless. These accusations are groundless and should not serve as a distraction from the position taken by the international community in its entirety, notably the United Nations. ECOWAS, the African Union, the European Union and IMF, Valero said. The United States and EU have slapped travel sanctions on Gbagbo and his inner circle, while the World Bank and the West African regional central bank have cut off his finances, which means he may soon have trouble paying troops.