The bilateral instrument which among other points anticipates a higher price for the power Paraguay sells to Brazil has yet to be ratified by the Brazilian Senate, where apparently the opposition is not willing to ratify.
Itaipu, the world's largest operational hydroelectric complex, is shared by Brazil and Paraguay, but the junior member only absorbs 10% of its 50% share of the power generated and the rest, by contract, is sold to senior partner Brazil.
This makes land locked Paraguay and one of South America's poorest countries one of the few in the world that has a huge energy surplus.
However the surplus is sold at prices dating back to the 1970s when the dam was built.
After months of discussions, sometimes irritating, the administration of President Lugo managed to convince Lula to triple the annual price paid for the energy, (US$ 120 million to US$ 360 million) plus other benefits such as a new high voltage line from Itaipu to blackout-castigated Asunción with an estimated cost of US$ 400 million plus two bi-national bridges.
Brazil has justified the fixed price for energy paid to Paraguay arguing that the country still owes its share of the costs of building the huge complex along the Paraná River over three decades ago.
The agreement also opens the Brazilian electricity spot market to Paraguay's Itaipu surplus share, which currently is totally absorbed by a Brazilian government power corporation.
Most of the energy is demanded by power hungry São Paulo, the industrial hub of Latin America's largest economy.
Lula has been lobbying strongly to have the agreement approved by Congress with the opposition claiming it will distort Brazilian industry costs in a highly competitive world.
"When Paraguay irritates Brazil, my job is to understand the situation and not act aggressively. Brazil is so much powerful and richer," said Lula.
"With Paraguay for Brazil is like a father-son relation. That is how large countries must act" towards smaller countries, argues the Brazilian president.
Mercopress