US imperialism is "already preparing the [military] attack", Venezuelan President Hugo Chavez warned, speaking to industrial workers in the region of Guayana on August 8.
The claim follows the recent announcement of a US-Colombia agreement to establish five new US military bases, to complement the two already there.
The announcement has been combined with the ramping up of a propaganda campaign to smear Venezuela as a country that aids terrorism, illegal arms trading and drug trafficking.
The Colombian government charged Venezuela with supplying weapons to the Revolutionary Armed Forces of Colombia (FARC), for which Colombian President Alvaro Uribe said Chavez should be charged in the International Court of Justice in The Hague.
The Venezuelan government has exposed in detail how the anti-tank weapons that were supposedly supplied to the FARC were actually bought by a previous government in 1988 and stolen during a raid by another Colombian guerrilla group, the National Liberation Army (ELN), in 1998.
Chavez was first inaugurated as president in 1999.
Chavez has made several calls on the FARC to enter into a political dialogue and lay down its arms. During his brief role in 2007 as mediator in the decades-long Colombian civil war, he negotiated the unilateral release of several FARC-held prisoners.
Chavez also said the Israeli government, through a recent tour of its foreign minister, Avigdor Lieberman, "had come to Latin America as part of the empire's plan".
Lieberman claimed cells of the Lebanese resistance group Hezbollah existed in La Guajira, near Venezuela's border with Colombia.
Chavez said Lieberman had "named the territory" to be attacked.
More alarmingly, Chavez denounced a recent "provocation" the following day on his weekly TV show, Alo Presidente, in which Colombian soldiers entered Venezuelan territory.
"We are not talking about a patrol with a few soldiers that strayed over a border", he said, but provided no more details.
Chavez said the US "is trying to convert Colombia into the Israel of Latin America" with Venezuela as its primary target.
Chavez reminded the industrial workers that "the Uribe government has already attacked Ecuador and bombed Ecuadorian territory".
In March 2008, an illegal military strike was carried out on a FARC camp in Ecuadorian territory. No attempt was made beforehand by the Colombian authorities to notify their Ecuadorian counterparts of the FARC presence.
Chavez also recalled the 2003 case of Rodrigo Granda, a FARC spokesperson arrested in Venezuela's capital, Caracas, with the involvement Colombian police officers who had illegally entered Venezuelan territory.
He compared the situation to a hypothetical scenario in which Venezuelan soldiers secretly entered the Colombian capital, Bogota, to arrest Pedro Carmona, the former head of the Venezuelan business federation, FEDERCAMAS.
Carmona is wanted in Venezuela for his role in a failed 2002 military coup that briefly installed him as dictator. He fled to the Colombian embassy and was granted asylum.
From Bogota, Carmona continued to openly conspire against the Chavez government.
Chavez also raised the issue of the 200 Colombian right-wing paramilitaries, linked to the Colombian government, that were sent to Venezuela to assassinate Chavez with the full knowledge of high-ranking officials in Uribe's government.
Chavez said the recent moves and allegations were "setting the stage for an aggression against Venezuela. And we will be obliged, if there is a military aggression against Venezuela, to also respond militarily.
"We will be left with no other alternative. Our response will be very firm."
He added that the Colombian people "have to be conscious of this because together we face the challenge of stopping war".
As a result of the recent dispute, Venezuela has frozen relations with Colombia and stopped the sale of subsided oil to its neighbour.