title: Venezuela has not told U.N. it is changing representative: official
text: NEW YORK (Reuters) - Venezuela s government has not officially notified the United Nations of any changes to its representation at the organization, a U.N. spokesman said on Wednesday.  Four sources told Reuters on Wednesday that Rafael Ramirez, a former oil czar turned U.N. diplomat, had been sacked from his post amid a broad oil industry anti-corruption campaign. 