Any deal for the Atletico Paranaense star will be done by The Magpies before they complete a move for Leeds United's Jonathan Woodgate.
Newcastle manager Sir Bobby Robson confirmed the interest in the pair.
"All I can confirm is that the club have actually made communication to both clubs in respect of the two players concerned," said Robson.
"There is a a lot of dialogue to go before the two possible transfers can be culminated."
Shepherd met with his Leeds counterpart Peter Ridsdale on Monday evening before flying out to South America to try and sign Kleberson.
Newcastle are believed to have agreed a deal in principle with Leeds for their England defender, but the North East club want their Brazilian target signed before they complete another deal.
23-year-old Kleberson has seen a move to Leeds flounder and now Newcastle are set to take the move on further and land him.
The Magpies are aware that Leeds are still interested in the player and so do not want to let the West Yorkshire club use any possible transfer funds from Woodgate, to launch a counter-offer.
Shepherd arrived in Brazil at 12:00 GMT and is now meeting with Atletico PR representatives.
Newcastle are able to offer immediate cash for the player and it is expected that they are likely to have Kleberson tied up within 24 hours.
It now seems that the only thing preventing Newcastle from sealing a deal for the Brazilian World Cup winner is a rival bid, which at this stage seems unlikely.
Woodgate, currently sidelined with a thigh injury, is the man Robson thinks can be the answer to their defensive frailties.
The Middlesbrough-born stopper is set to talk terms on his prospective move to St James' Park upon, Shepherd's return to England later this week.
