Increasingly concerned about an oil shortage as a possible war with Iraq approaches, the Bush administration has overcome its reluctance to become involved in Venezuela's escalating political conflict and is preparing a major initiative it hopes will lead to a breakthrough in deadlocked talks between the government and opposition there, according to U.S. and foreign diplomatic sources.

The U.S. initiative is centered on the formation of a group of "Friends of Venezuela," trusted by one or both sides to the conflict, that would develop and guarantee a compromise proposal, based on early Venezuelan elections presented through an existing mediation effort by the Organization of American States.

The initiative is expected to be rolled out within the next week. Its immediate goal would be an end to an opposition-organized strike, in its second month, that has paralyzed the Venezuelan economy and stopped all petroleum exports, including the 1.5 million barrels a day to the United States, about 15 percent of U.S. oil imports.

The administration also hopes to head off a budding Venezuela initiative by Brazil's new left-leaning government that it and many others in the region believe would be counterproductive, sources said. Brazil would be part of the new group, along with the United States, Mexico, Chile and possibly Spain, and a representative of U.N. Secretary General Kofi Annan.

Secretary of State Colin L. Powell has held discussions in the past few days with Mexican Foreign Minister Jorge Castaneda, as well as with Brazilian officials, Annan and OAS Secretary General Cesar Gaviria, who has been mediating talks in Caracas between the opposition and the Chavez government.

Those talks are stalled on the fundamental issue of whether, and how, Venezuelan President Hugo Chavez remains in power. Beyond outright resignation, which Chavez has rejected, the Venezuelan constitution offers two alternatives: a constitutional amendment, agreed by the legislature and approved by popular vote, for early elections; or a referendum on whether the president should stay in office, which could not be held until halfway through his term, in August. If Chavez lost, he would be replaced by his vice president and new elections -- in which Chavez could not run -- would have to be held in 30 days.

Chavez has expressed confidence he would win any new vote, and has said he would agree to the latter option. But the opposition believes August is too far off, and in any case it doesn't trust Chavez to follow through. A senior State Department official said that the administration could support either option, but wants something to be agreed to soon that would stop the strikes and street demonstrations. The U.S. hope, sources said, is that each side would have confidence in and adhere to an agreement guaranteed by the powerful new "group of friends."

Powell said in an interview Wednesday that he was working "to try to get some movement in Venezuela." But he declined to characterize his efforts beyond saying, "We're just trying to put a little more ooomph behind what Gaviria is doing."

The administration has treated the Venezuelan situation gingerly since last spring, when it was accused of reviving a long history of U.S. meddling in the region during an aborted coup attempt against Chavez. Since then, despite opposition assumptions of support, it has rigidly limited itself in public -- and largely in private -- to supporting the OAS effort, according to informed sources.

Although it basically agrees with opposition charges that Chavez, a populist former military officer, has threatened democracy and the economy and has moved the country too far to the left, the administration's concern about wider fallout from the upheaval there has overtaken its worries about Chavez's politics.

"We were getting 1.5 million barrels of oil each day, and we're not getting it now," the senior State Department official said. Concerns have multiplied over the past week as Chavez moved to fire senior oil executives and restructure the state-owned oil enterprise, the official said.

The official also said that as the strike continues and expands, widespread violence will become more likely. The official said there is concern that the situation "slips the leash" from controlled protest to violent chaos, he said. The longer it goes on, the harder it will be to put Venezuela back together, he said.

But it has been the success of the oil strike, and the recent firings and structural changes, that have changed U.S. direction, said a foreign diplomat involved in the situation. As far as the Americans are concerned, the diplomat said, the situation moved "from a problem in an important country in Latin America to a very critical matter. . . . With the war in Iraq, it became a really strategic matter."

Brazilian President Luis Inacio Lula da Silva has not yet agreed to the U.S. idea, sources said, and is awaiting a meeting he has called for Wednesday when regional leaders gather in Quito for the inauguration of the newly elected president of Ecuador.

It was at Lula's inauguration last month that Chavez announced he favored an international diplomatic effort to resolve the Venezuelan conflict, to include countries in Latin America, Europe and the Organization of Petroleum Exporting Countries, or OPEC, which Venezuela helped found more than four decades ago.

Lula appeared to agree. But much of Latin America and Gaviria consider it an attempt by Chavez to stack the deck with sympathizers and undercut the OAS. The United States immediately rejected the idea.

"We don't think there needs to be some separate group of friends formed," said State Department spokesman Richard Boucher, noting that the OAS was "uniquely positioned and equipped to address Venezuela's crisis of democracy."

Latin American sources said there is little desire to involve any government outside the hemisphere, except perhaps Spain.

At the same time, Latin American sources said, it is widely believed that any high-level intervention in the OAS effort that does not include the United States is unlikely to bring the opposition to agreement.

The U.S. initiative, sources said, is designed to add muscle to Gaviria's mediation rather than undermine it. In a brief interview yesterday by telephone from Caracas, Gaviria said he thought the idea of a "group of friends . . . is good" as long as it works within the OAS framework.

But the initiative has potential problems because of convoluted regional relationships.

Both the Bush and Lula administrations recognize their bilateral ties could be problematic and are eager not to antagonize each other. Brazil and Mexico, Latin America's two largest countries, are competitors for regional leadership. Cuba, one of the countries closest to Chavez, receives highly preferentially priced oil from his government, as do many smaller island governments in the Caribbean. All fear a solution that results in Chavez's removal might threaten those deals; together, they make up a major OAS voting bloc.

Juan Fernandez leads striking Venezuelan oil workers in a demonstration in Caracas. Strikes against President Hugo Chavez have lasted more than five weeks.