The United States is considering financial sanctions on Venezuela that will halt dollar payments for the country's oil, according to a senior White House official and an adviser with direct knowledge of the discussions.

The move could severely restrict the OPEC nation's crude exports and starve its socialist government of hard currency.

Sanctions prohibiting any transaction in U.S. currency by Venezuela's state-run oil firm, PDVSA, are among the toughest of various oil-related measures under discussion at the White House, the two sources said.