Ariarne Titmus breaks women's 400m freestyle world record at Australian Swimming Championships

Two-time Olympic champion Ariarne Titmus has broken the women's 400m freestyle world record at the Australian Swimming Championships.

The 21-year-old clocked a time of 3 minutes 56.40 seconds on the final evening of competition in Adelaide on Sunday (22 May).

That time is 0.06 seconds faster than Katie Ledecky's world record, which had been set in the Rio 2016 Olympic final nearly six years ago.

However, Titmus will not go up against Ledecky at next month's World Championships in Budapest despite qualifying with her performance today, as the Australian has previously said she will skip Budapest to focus on the Commonwealth Games in Birmingham, England, in July.

Swimming in her pet event, Titmus – whose previous personal best was 3:56.69 set last year – was dominant and touched home nearly six seconds ahead of second-placed Lani Pallister.

"I never thought at this meet post the Olympics I'd be swimming faster than the Olympic trials and the Olympic Games," Titmus told broadcaster Amazon Prime after the race. "I guess if you keep surprising yourself, it keeps the sport interesting."

It was the second world record set this week in Adelaide, after Zac Stubblety-Cook's performance in the men's 200m breaststroke.