By Gary Duffy
BBC News, Sao Paulo
President Lula is expected to sign deals on defence with Mr Sarkozy
Leaders from the European Union and Brazil are expected to focus on the financial crisis and climate change at a two-day summit in Rio de Janeiro.
French President Nicolas Sarkozy will attend, as well as European Commission head Jose Manuel Barroso.
On Tuesday, Mr Sarkozy and Brazilian President Luiz Inacio Lula da Silva are expected to sign a range of agreements.
They may include one that would help build South America's first nuclear propelled submarine.
In an interview just ahead of his arrival, Mr Sarkozy - who currently holds the EU's rotating presidency - was keen to stress the growing importance of Brazil's role in the world, words that will undoubtedly please his hosts.
He told the newspaper Folha de Sao Paulo that no-one could imagine resolving problems today "without involving China, India and, of course, Brazil".
His emphasis on the need for a new system of world governance, and one that would be more open to developing countries, will also be welcome here.
It was not an option, he said, but a necessity which should be dealt with urgently.
As well as the financial crisis, the issue of climate change is likely to figure prominently in discussions with the European leaders.
Mr Sarkozy will also have separate meetings with President Lula on Tuesday at which the two leaders are expected to sign a range of agreements, most notably relating to defence.
Last week, Brazil unveiled a new strategy to upgrade the country's defence policy, and the government is keen to forge partnerships with nations that are willing to share technology.
Mr Sarkozy's wife, Carla Bruni, is likely to attract huge media interest
According to reports in the Brazilian media, the two presidents will sign an agreement that will help build South America's first nuclear propelled submarine.
With Brazil making extensive oil finds off its coast, the government here is becoming increasingly preoccupied with defending the country's coastal waters.
Another potential agreement is said to include the transfer of French technology to help build four conventional submarines.
The meetings will take place in Rio de Janeiro's famous Copacabana Palace hotel, and there is expected to be huge media interest in the activities of the French president's wife, Carla Bruni, as she carries out a range of functions in the city.