BRASILIA, Brazil (AFP) - Chinese Premier Li Keqiang and Brazilian President Dilma Rousseff inked a series of trade and investment deals Tuesday worth billions of dollars, officials said.

The deals, part of a US$50 billion (S$66.7 billion) Chinese investment package, included a pair of finance and cooperation deals worth US$7 billion for Brazil's state-owned oil firm Petrobras.

China has since 2009 been Brazil's main trade partner and Chinese commodity demand fuelled a surge in Brazilian growth prior to a slowdown that is now in its fifth year.

But China currently ranks only 12th in terms of actual investment in Brazil, prompting Brasilia to seek deeper economic ties as it looks to overhaul creaking infrastructure in time for next year's Olympics in Rio de Janeiro.

At their talks, aside from the Petrobras agreements, Rousseff and Li also signed a range of deals designed to further bilateral cooperation on trade, investment, agriculture, energy and transport, government sources said.

Brasilia and Beijing also finalised a US$1.3 billion accord to sell 22 Brazilian Embraer commercial jets to China's Tianjin Airlines, Embraer said in a statement.

On Thursday, after first inspecting Chinese investments in Rio, including new metro trains, Li will continue a Latin American swing designed to promote Chinese interests in the region, heading to Colombia before visiting Peru and Chile.

His tour comes days after Beijing signed accords worth US$25 billion and US$22 billion respectively with fellow Brics developing nations Russia and India.