Washington has distanced itself from the comments which have outraged Venezuelan authorities, who expressed concern about Mr Chavez’s safety when he travels to the UN General Assembly in New York next month.
Speaking from Cuba, President Chavez said he would not be drawn on the comments, however his deputy said the country is studying its legal options.
Mr Robertson, who founded the Christian Coalition and is a former presidential candidate, said during last night’s television broadcast of his religious program The 700 Club that Mr Chavez poses a great danger to the US.
He said the leader is turning his oil-rich country into a “launching pad for communist infiltration and Muslim extremism all over the continent.”
He did not substantiate the allegations.
“We have the ability to take him out, and I think the time has come that we exercise that ability,” he said.
“We don’t need another $US200 billion ($A265.22 billion) war to get rid of one, you know, strong-arm dictator,” he continued.
“It’s a whole lot easier to have some of the covert operatives do the job and then get it over with.”
US Defence Secretary Donald Rumsfeld denied the Pentagon has considered assassinating the leftist Venezuelan president.
“Our department doesn’t do that type of thing,” he said.
The US State Department described the comments as “inappropriate”.
“I would say that Pat Robertson is a private citizen and that his views do not represent the policy of the United States,” said State Department spokesman Sean McCormack.
“As we have said before, any allegations that we are planning to take hostile action against the Venezuelan government are completely baseless and without fact,” Mr McCormack added.
But Venezuela’s ambassador to the US, Bernardo Alvarez, has demanded stronger condemnation of the comments, saying Mr Robertson is no ordinary citizen and is the former leader of a massive pro-Bush Christian grouping.
President Chavez has frequently criticised the US, accusing Washington of conspiring to topple his government and even backing plots to have him assassinated.
The US sees Venezuela as a potential source of regional instability.
Venezuela is the world’s fifth largest oil exporter and a major supplier to the United States.
Robertson has frequently made controversial comments, once declaring that feminism “encourages women to leave their husbands, kill their children, practice witchcraft, destroy capitalism and become lesbians.”