Telesur (Telesouth), a Spanish-language station formed by the governments of Venezuela, Argentina, Cuba and Uruguay, began transmissions on Sunday with round-table commentary from the station's officials and an advisory board of international left-wing intellectuals and celebrities.
"We launch Telesur with a clear goal to break this communication regime and present a vision, a voice which until now has been silenced. Telesur is an initiative against cultural imperialism," Andres Izarra, Telesur president and Venezuela's minister of communications, said.
The Venezuelan-financed venture aims to provide a Latin American perspective on events, promote cultural diversity, and counter what its creators call the hegemony of international and local commercial networks in their coverage of the region.
Chavez, an outspoken left-wing nationalist who often accuses US President George Bush of plotting to topple him, called the launch a success and said Telesur was vital to his vision of Latin American and Caribbean integration.
He said the channel was drawing viewers from around the region and that even Bush was "glued to the television watching Telesur".
Relations with the United States, the top buyer of Venezuela's oil, have deteriorated since Chavez first won office in 1998 and strengthened relations with Communist Cuba.
The US gets around 15% of its oil imports from Venezuela, the world's No 5 crude exporter.
Chavez said the network was a blow to an effort by some US legislators trying to wage what he has called "electronic warfare" against him.
Last week, the US House of Representatives adopted a bill with an amendment that authorises broadcasts to Venezuela to counter what one US lawmaker called the "anti-American, anti-freedom rhetoric" of Chavez.
Backers of the measure hope to get the Senate to approve their version of the legislation.
"The United States has threatened us with broadcasts to neutralise Telesur. We have scored the first goal"
"The United States has threatened us with broadcasts to neutralise Telesur. We have scored the first goal," Chavez said in a telephone call to the channel during the launch.
Telesur advisory board members attending the broadcast included British left-wing intellectual Tariq Ali, Le Monde Diplomatique editor Ignacio Ramonet, and US film star Danny Glover. Other advisory board members include Nobel Peace Prize winner Adolfo Perez Esquivel and Uruguayan writer Eduardo Galeano.
Chavez also defended Telesur against critics who say it will become a propaganda mouthpiece for his self-styled "revolutionary" government and for his Caribbean ally, Cuban President Fidel Castro.
"I am sure that Telesur will maintain its independence. Telesur will not depend on any government ... it will be free to navigate in the waters of truth and contribute to the construction of a new world," Chavez said.