Major international oil companies agreed to cede control of Venezuela's last privately run oil projects to President Hugo Chavez's government, but ConocoPhillips resisted, prompting warnings its fields could be taken over outright. Chavez decreed last month that four heavy-oil projects in the Orinoco River basin, considered Venezuela's most lucrative, be brought under government control on May 1. The president has said soldiers will accompany officials to the fields on that day. Officials from Chevron Corp., BP PLC, France's Total SA and Norway's Statoil ASA signed memorandums of understanding Wednesday agreeing to give state oil company Petroleos de Venezuela SA a majority stake in three of the projects. Exxon Mobil Corp. signed earlier in private, officials said. But Venezuelan Energy Minister Rafael Ramirez said at the ceremony that Houston-based ConocoPhillips has yet to sign an agreement.