Venezuelan President Hugo Chavez warned Friday that it would be madness for the United States and its NATO allies to go to war in Libya to try to topple Moammar Gadhafi.

Chavez, a friend and ally of Gadhafi, criticized President Barack Obama for expressing support for the Libyan opposition.

"Right now they are preparing a war, the Yankees and their NATO allies," Chavez said in a televised speech.

He predicted a larger war in Libya could push world oil prices to $200 a barrel, and he echoed Gadhafi's warnings that a foreign military intervention would unleash much more bloodshed.

"If the Yankees (attempt) the madness of invading Libya — Gadhafi already said it a few days ago — it would be a new Vietnam," Chavez said.

The Venezuelan president has proposed forming a "humanitarian commission" to travel to Libya to seek a peaceful resolution to the conflict.

His stance has been echoed by Latin American allies including Cuba, Ecuador and Bolivia. But other countries have dismissed Chavez's mediation idea, and rebels in Libya have not expressed willingness to negotiate as long as Gadhafi remains in power.

Obama said Friday in Washington that the U.S. and the world community are "slowly tightening the noose" on Gadhafi. It was not clear what next steps Obama might be willing to take, but he said he was considering all options, including military efforts with NATO partners.

"Today I saw Obama, the Nobel Peace Prize winner, saying that he's concerned about the price of oil," Chavez said.

Chavez has accused the U.S. of maneuvering to seize control of Libya's oil. He said he believes events in Libya are being distorted to lay the groundwork for a conflict, and likened it to the situation in Venezuela in 2002 when he survived a failed coup.

"In its desperation, the Yankee empire is continuing and will continue to threaten nations that struggle for their dignity ... conspiring against governments," Chavez said.

He said his proposal for a peace effort would respect "the self-determination and freedom of Libya, which is a sister nation."

As for the conflict raging in Libya, Chavez said: "That's a matter the Libyans should resolve."