Venezuelan President Hugo Chavez has been visiting Russia in an attempt to boost economic, energy and military ties between the two countries.
Mr Chavez attened the opening of a Latin American culture centre
Mr Chavez's visit came as Russian officials indicated the two sides were discussing Venezuela's possible purchase of five Russian submarines.
The Venezuelan leader invited Russian companies to help develop his country's oil fields in the Orinoco Basin.
President Chavez has now gone to Belarus and is also due to visit Iran.
The Venezuelan president arrived in Moscow on Wednesday amid widespread speculation that he was interested in signing an arms deal with Russia.
There was no official announcement but Russian officials, quoted by the RIA-Novosti news agency, said the two sides were discussing the possible purchase by Venezuela of five diesel submarines.
Venezuela has previously bought fighter planes, helicopters and assault rifles from Russia.
Mr Chavez is also interested in Russia's oil and gas knowledge and the two nations had specific energy issues to discuss.
Mr Chavez at one pointed referred to Mr Putin as "brother"
"We are very satisfied with the presence of Russian companies in our oil industry and will do our best to develop this co-operation further," the Venezuelan leader told Russia's Chamber of Commerce and Industry.
Mr Chavez said he and Russian President Vladimir Putin had agreed to create a fund to support joint projects. With Russia's help, Venezuela was set to build four oil refineries and plans a further 13, the Associated Press quoted him as saying.
Russian gas giant Gazprom and oil giant Lukoil are already working to develop projects in Venezuela.
This week, two US companies, Exxon Mobil and ConocoPhillips, rejected government terms for operating in Venezuela and pulled out of exploration ventures.
The Orinoco belt in Venezuela holds the world's largest reserves of heavy oil.
During his Moscow visit, President Chavez used a colourful ceremony opening a Latin American cultural centre in Moscow to rail against "US tyranny" and stress the friendship between his country and Russia.
"We, like you, are fighting for a fair world based on respect for all peoples. American imperialism is destroying peoples, undermining their traditional cultural values," Mr Chavez said.
Mr Chavez's visit came just days before Mr Putin is due to hold key talks in the US with President George W Bush on tensions over US missile defence plans.
In a sign the Kremlin aimed to keep Mr Chavez's visit relatively low-key, the Duma, the lower house of the Russian parliament decided not to invite the Venezuelan leader to address the full chamber.
"It appears the Kremlin doesn't want to irritate the White House on the eve of the Kennebunkport meeting," the Kommersant newspaper wrote.