He spoke shortly after Venezuela's top electoral officer, National Electoral Council President Francisco Carrasquero, announced to the nation preliminary official results showing that Chavez had survived the recall vote.
Carrasquero said in a national broadcast the "No" option opposing Chavez's recall had obtained just over 58 percent of the vote, while the "Yes" vote obtained nearly 42 percent.
"Our numbers ... are very different," Ramos said, adding the opposition would ask international organisations who observed the referendum to check the voting machines and ballots.
Two pro-opposition members of the five-member National Electoral Council leadership earlier also questioned the result and said certain required checks had not been carried out - probably refering to the finger print checks that were abandoned early on due to technical difficulties and the failure of the contracted technicians to turn up to operate them.
The sheer number of voters, along with the problems with electronic thumb-printing machines, overwhelmed election authorities, who postponed the polls' closing to midnight, eight hours later than originally scheduled.
There was no immediate reaction from former US President Jimmy Carter or Cesar Gaviria, head of the Organisation of American States, who helped monitor the vote.
Meanwhile.. "Long live the constitution ... of Venezuela," Chavez said. "Long live the Venezuelan people. What a great victory."
Many opposition supporters were apparently in tears at their defeat and some may take to the streets in protest.