(Dow Jones) - "State oil firm Petróleos de Venezuela has taken an average stake of 78% in four multi-billion dollar extra-heavy oil projects in Venezuela's Orinoco belt, PdVSA said in a statement, effectively doubling its previous average equity interest in them.

PdVSA noted that ConocoPhillip's (COP) Petrozuata project will come under PdVSA's 'total control,' and makes no mention of ExxonMobil, which, like Conoco, has resisted the state's push to make foreign oil majors minority partners in the projects.

'Of the multinationals that accepted the negotiation with the state oil industry, it must be remembered that France's Total (TOT), and Norway's Statoil (STO) participated in Sincor with 47% and 15% (stakes), respectively, while the U.S. 's ChevronTexaco (CVX) had a 30% stake in Ameriven. For its part, BP Plc had a 16.67%' in Cerro Negro, PdVSA said in its statement.

Exxon had a 41.7% stake in Cerro Negro, while PdVSA had a 41.6% interest.

President Hugo Chávez's move to control these ventures comes as part of a larger nationalization campaign of 'strategic' sectors, which also include the electricity and telecommunications sectors.

His administration had originally announced it would seek at least a 60% stake in each of these joint ventures (...)