The Organization of American States and Carter Center say they will not send observers to Venezuela's gubernatorial and municipal elections later this month.
Venezuelan authorities recently invited the two organizations to oversee the elections.
But the OAS and Carter Center said they do not have enough time to organize an observer mission with the vote scheduled for October 31.
The Carter Center, however, also cited the Venezuelan opposition's refusal to accept its validation of President Hugo Chavez's victory in an August 15 recall vote.
The Carter Center reported it saw no evidence of fraud in the vote.