"It's our second game in this tournament and I do not see this having a lot to do with the Ashes. It is an important knock-out game for both teams," Ponting said on Friday.
"Once we go back to Australia, we will probably start worrying about the Ashes. Right now, we are focussing on tomorrow's game."
England were dismissed for just 125 in the opening match of the tournament against India, eventually going down by four wickets, while Australia also lost their first match against the West Indies, falling 10 runs short in their chase for 235.
Flintoff agreed with his Australian counterpart's comments, saying his side were concentrating on the Champions Trophy rather than the Ashes which begin in Brisbane on November 23.
"We are playing a big one-day international against Australia in an important competition tomorrow, so we are focussing on that," said Flintoff.
"To be honest, I am not looking too far ahead as we have got a game tomorrow and that's where we are concentrating. Once the competition is out of the way we will focus our attention on the Ashes."
England have won just six out of the past 27 one-day internationals they have played, however Ponting felt that the old enemy would definitely be up for Saturday's crucial match.
England's Andrew Flintoff is just
focusing on the Champions Trophy
"Their one-day form probably has not been good, but a lot of those things don't matter when you have a contest like this," said Ponting.
"Both teams are pumped up. Anything can happen on such days.
"We were in exactly the same situation in the 1999 World Cup when we had to win every game after the qualifying round," the 31-year-old added.
"What it tends to do is bring the best out of us. We tend to play our best cricket when we are under pressure."
Flintoff said that his side were looking forward to doing battle with the World Champions, especially the players who had not played against Australia previously.
"We enjoy testing ourselves against the world's best players. We have got some guys who have not played against them and they are going to go out there and try to impress and perform," said Flintoff.
"It's going to be a tough game. They (Australia) have got some great players in their ranks and they play their cricket hard.
"They are slight favourites, but it is all about who is going to hold their nerve tomorrow."