Chavez, a fierce critic of US President George Bush and the US-led war in Iraq, on Saturday brushed aside US opposition to the agreement to buy 100,000 automatic rifles and about 40 military helicopters from Moscow.
"One has to ask whether there was transparency in the invasion of Iraq. The world knows President Bush lied openly about Iraq having chemical weapons," Chavez said.
"They keep on bombing cities, killing children, they have become a terrorist state," he said.
Venezuela, the world's fifth largest oil exporter, is a key crude supplier to the US. But relations soured after Chavez came to power in 1999, vowing to fight poverty with a self-proclaimed revolution.
US officials have accused Chavez of allowing Marxist rebels from neighbouring Colombia to shelter in Venezuela and criticise his increasingly close relations with Cuban leader Fidel Castro.
Chavez, however, rejects the charges and has moved to strengthen Venezuela's political and economic ties beyond Washington with states such as China, Russia and Iran.