Venezuela is buying more Russian weapons, including armored personnel carriers and tanks, to replace aging ordnance and to improve the country's security and defense capabilities, a top military commander said Thursday.

"We could be talking about 100 to 500 tanks. Right now it's impossible to know ... because strategic research studies are still underway (and) we're still negotiating," Strategic Operations Command chief General Jesus Gonzalez told reporters.

The general was confirming an Interfax news agency report Wednesday about a Russian weapon shipments to Venezuela, which Russian arms export agency deputy director Igor Sevastyanov said included "a large number of BMP-3 armoured personnel carriers" and multiple rocket launchers.

The move follows increasingly closer Russian-Venezuelan relations and 4.4 billion dollars in bilateral arms deals signed since 2005 that have raised US concerns, especially in view of Venezuelan President Hugo Chavez's fierce anti-American stance.

After meeting with a visiting top-level Russian delegation headed by Security Council secretary Nikolai Patrushev, Gonzalez said "nobody should be surprised or afraid" about the arms deal and growing friendship between the two countries.

"Our security and defense require the purchase of airplanes, helicopter and tanks," he added without mentioning a price tag for the recent weapons deal.

Moscow, he said, "is now supplying us with the materials we need for our defense," including armored personnel carriers.

He said Venezuela needed tanks "because the French AMX tanks we got 30 years ago are quite old now, and the Scorpio tanks from Britain are also quite old. We're buying mid-sized T-62 (Russian) tanks ... reconnaissance tanks and other models offered us."

Venezuela and Russia's "decision to have bilateral, technical-military trade is firm and permanent," the Venezuelan general stressed.

Venezuela has already bought 24 Sukhoi fighter jets, 50 helicopters and 100,000 Kalashnikov assault rifles from Russia.

During a visit by Venezuelan President Hugo Chavez to Moscow last month, Russia announced it was giving Venezuela a one-billion-dollar credit to buy Russian weapons and the two countries discussed nuclear energy cooperation.

They are also planning joint naval exercises in the Caribbean in November.

US military chiefs have said they are concerned about the military build-up in Venezuela and the US State Department has said it will be watching the Russian-Venezuelan naval exercises "very closely."