In November, Venezuelan President Hugo Chavez said that Russia had agreed to lend his country over $4 billion to buy weapons.
"There is a contract with Venezuela but it's not yet being implemented," Rosoboronexport special programs director Nikolai Dimidyuk told reporters.
"Venezuela has rescheduled the dates several times, but now we have agreed on a timeframe for the deliveries," he added.
Venezuela is one of the biggest buyers of Russian arms.