Ponting hit 111 not out and Shane Watson thumped an unbeaten 136, the pair sharing an unbroken second-wicket partnership of 252 to set Australia up for a final meeting with New Zealand or Pakistan on Monday.
"(Passing 12,000) is a nice little achievement I guess but I'll look at it when I have finished playing," Ponting said at the post-match presentation.
"(Squad member) Dave Hussey came out (to the middle) tonight and said, 'I wanted to tell you that you were getting close to 12,000 runs'. I had no idea, it's never been anything that motivates me, personal stats.
"It is about doing a job when it matters for the team so I'm happy I have been able to do that today," added Ponting.
The 34-year-old, who joins India's Sachin Tendulkar and Sanath Jayasuriya of Sri Lanka in achieving the milestone, led from the front as Australia reached their target of 258 with 8.1 overs to spare.
WATSON RELIEF
All-rounder Watson's innings came as a relief to the opener after a run of patchy form with the bat.
"I hadn't had a great start to the tournament at all although I felt my bowling was quite good. So it was good to get going today and nice to bring the team home," said Watson.
"I have been lucky to play in a few big games for Australia although I haven't played as much of a part in them as I would have liked. Today I wasn't too overawed, as I have been previously."
England captain Andrew Strauss accepted his team were well beaten after they had been bowled out for 257 in 47.4 overs.
"It was a very good pitch and we definitely wanted to play shots but it just didn't work for us," he said. "It was very frustrating to lose our first six wickets for 101 runs but I guess you live by the sword and die by the sword.
"We've got to keep playing shots and improving our skills. It just didn't gel for us today."
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