Bolivia is under pressure to reassure South American and European trading partners about its nationalization of the natural-gas industry, ahead of an emergency summit of South American leaders over the move. Acknowledging the uproar the nationalizations caused, Bolivian President Evo Morales sought to calm fears over gas supplies and possible expropriations. He planned to discuss the issue with leaders of three other South American countries, including Venezuela's Hugo Chavez, a close ally who also has tightened state controls over the energy sector in his oil-rich country. Brazilian President Luiz Inacio Lula da Silva and Argentine President Nestor Kirchner, whose countries rely heavily on Bolivian gas, also will participate in Thursday's meeting in northern Argentina. The Brazilian government on Tuesday held an emergency meeting with Brazil's Petrobras, which is the largest foreign investor in Bolivia and manages 75 percent of the country's natural-gas exports. Morales emphasized that Bolivia would “guarantee gas [supplies] to Brazil and Argentina.” He also insisted that the nationalization affected natural resources, not company installations. “There is no confiscation or expropriation of company property,” he told the Venezuela-based Telesur network on Tuesday. “Their installations will continue to be their installations.” Under Morales' nationalization order, foreign companies have up to 180 days to renegotiate their contracts with state-run Yacimientos Petroliferos Fiscales Bolivianos (YPFB), which will become the majority shareholder in the reformed corporations. The European Union (EU) on Wednesday urged Morales to hold negotiations with the affected companies, which include oil and gas giant Exxon Mobil, Brazil's Petrobras, Spain's Repsol, Britain's BP and British Gas, and France's Total. The EU voiced “concern” at Bolivia's decision Monday to deploy troops at 56 oil and gas fields, and said in a statement that it would “remain attentive to the issue during the coming months.”