Venezuelan leader told reporters, noting that he hoped to ink other agreements on agriculture, oil and mining during his visit to Moscow in mid-September.
Between 2005 and 2007, Moscow and Caracas signed 12 arms deals worth a total 4.4 billion dollars. Venezuela has acquired 24 Sukhoi fighter planes, 50 combat helicopters and 100,000 Kalashnikov assault rifles. In 2008, it secured a one-billion-dollar loan for the purchase of new weaponry.
Under the new deal, Venezuela would buy a modern battalion of "30 to 40" Russian-made BMP-3, T-72 and MPR tanks, Chavez said following a telephone conversation with Russian Prime Minister Vladimir Putin.
"Our army will continue to grow," vowed Chavez, who is leading a leftist surge in Latin America and repeatedly lambasts the United States for perceived "imperialist" policies in the region.
Chavez denounced Colombia's plans to open seven bases on its soil to the US military to boost Washington's counternarcotics operations in the region, calling them "a threat."
"I do not want to spend a penny on arms, and that is what I did in the early years of the government... But the (US) empire wanted to disarm us and if not for Russia, we would be virtually unarmed," he said.
Bogota's plans have been met with fierce opposition in South America, prompting Colombian President Alvaro Uribe, a close US ally, to undertake a regional tour this week to tamp down the criticism.
Chavez expressed "frustration" with President Barack Obama over the deal, saying his government has been "assaulted" by the new US administration.
"The policy of aggression against Latin America is the same... It's as if no change had occurred from (former president George W.) Bush to Obama. It's all the same," he said.
The firebrand leftist ordered a halt to the import of 10,000 cars from Colombia, in a further sign of growing frictions between the neighboring countries.
Last week, Chavez recalled his ambassador from Bogota and announced a "freeze" in relations between the two countries, after Colombia claimed that anti-tank rocket launchers sold to Venezuela in the 1980s ended up in the hands of the FARC, a Colombian leftist guerrilla group.
Venezuela and Russia signed an agreement in Caracas in late July boosting their military ties, including through arms purchases, joint maneuvers and military technology.
Russia was given an opportunity to increase military ties with Venezuela after former US president George W. Bush's administration reduced arms sales to the South American oil exporter in 2006 because of what it said was insufficient cooperation from Caracas in the US "war on terror."
Chavez in March also offered Venezuelan air bases for use by Russian long-range bombers.
In November last year, the navies of Venezuela and Russia pointedly held joint exercises in the Caribbean -- traditionally considered a US domain.