Warner has expressed his desire to play his last Test in Sydney against Pakistan in January next year though he wants to play on until the 2024 Twenty20 World Cup.
Australia have already retained the Ashes urn taking a 2-1 lead heading into the final Test, and former England captain Michael Vaughan is among those who believe the duo could exit after the match at the Oval.
Warner, talking to reporters on the eve of the match, called it a "joke".
"And Smithy (is retiring) too apparently. So obviously it's a joke," Warner said.
"I won't take that too seriously ... I don't have an announcement."
A fixture at the top of the Australian order since his debut in 2011, Warner has managed 201 runs in the ongoing Ashes series averaging 25.12 with a top score of 66.
"I've probably left a few out there but in saying that, I've played a lot better than what I did last time," Warner said.
"I feel like I'm in a good space, contributed well, and as a batting unit we're all about partnerships, and I think the partnerships that we've had in key moments of this series have actually worked very well for us as a team."
Warner knows he is near the end of his Test career and the 36-year-old backed Matt Renshaw to succeed him and dominate both Test and one-day formats like Australia great Matthew Hayden did in his playing days.
Australia's captain Pat Cummins also dismissed the "completely made up" suggestion that Warner and Smith would walk away at the Oval and said they were focused on the task at hand.
"It's a big week," the fast bowler said.
"If we win this one and you look back, it's been an incredible tour over."
"It's already a fantastic tour. But to go home winning the urn will be phenomenal.
"It's a final thing to tick off the list of titles to win for a few of the guys. You never know if you'll get another chance to do it."
