On Thursday, Connie Mack, a Florida Republican, criticised the agreement between Aljazeera and Telesur to share content and co-operate in gathering news.
But an official in Caracas said Mack's criticism was "a direct insult to the governments of Venezuela, Argentina, Cuba and Uruguay".
In a statement on his website, Mack had said: "When Hugo Chavez launched Telesur last year to spread his anti-freedom rhetoric throughout Latin America I raised numerous concerns that he was creating a TV network patterned after Aljazeera.
"Today, Hugo Chavez has gone even further.
"It wasn't enough for him to spread his socialist propaganda throughout Latin America. Now he's in cahoots with the original terrorist TV."
Yuri Pimentel, Venezuela's information minister, said on Thursday that Mack's statements "represent a veiled threat of an airstrike, similar to the bombing that George Bush announced against the Aljazeera headquarters".
Aljazeera has demanded an investigation into British media reports that President Bush considered bombing their network headquarters. The White House, which says the network presents biased accounts of Middle East developments, denied the reports as "outlandish and inconceivable".
Telesur, based in Caracas, aims to provide an alternative to the privately held media that Chavez has accused of US-biased coverage.
Aljazeera recently opened its first Latin American bureau in Venezuela's capital.
Aram Ahoranian, Telesur's station manager, said the network had a total budget of $10 million last year, with 51% funded by Venezuela and the rest by Argentina, Uruguay and Cuba.
"We continue to believe in democracy, freedom of expression, and pluralism: all the values that are indispensable in any democracy"
Telesur station manager
Ahoranian said: "We continue to believe in democracy, freedom of expression, and pluralism: all the values that are indispensable in any democracy.
"We don't have any problem making agreements with any organisation that is beneficial for our channel."
In July, the US House approved a measure sponsored by Mack authorising the government, if necessary, to initiate radio and television broadcasts to counter Telesur and "provide a consistently accurate, objective, and comprehensive source of news".
Chavez has vowed to jam the signals if the US tries to transmit them to Venezuela.
Mack urged the Senate to approve the measure, saying the United States "must counter the tyrannical, anti-democratic messages that this dangerous alliance will spew to Latin America and the entire world".
Chavez maintains that his government is fully democratic and accuses Washington of being the real threat to the region. He says Telesur will help to give South America an independent voice.