Phelps set a record of eight Olympic gold medals -- beating Mark Spitz's mark of seven from Munich in 1972 – at the Beijing Games.

But the 100m freestyle was not among his conquests as former world record-holder Bernard claimed that ahead of Australia's Eamon Sullivan.

Bernard actually set a world record in the semi-finals in China only to be bettered by Sullivan in the very next semi, although the Frenchman had the last laugh when he won the gold medal the next day.

Now Phelps told Gazzetta dello Sport that he may take on Bernard in next July's World Championships in Rome.

"Someone like Bernard is right on my heels; I missed his (former) world record by a hundredth of a second, it could be a great challenge in Rome," said Phelps.

"There are lots of competitors. I also respect your (Italian Filippo) Magnini (a double world champion at 100m free) who left me fifth in Montreal (the 2005 World Championships).

"But right now swimming is a world away from my thoughts although I still want to push myself to the limits."

Phelps said he and his coach Bob Bowman would be taking a substantial period of time off.

"We both need it, we've finished a huge workload," he added.

Phelps also said he would change his focus from longer to shorter races.

In Beijing he won the 400m medley, 200m freestyle, butterfly and medley, 100m butterfly as well as three relays.

But when asked what other challenges lay ahead he focused on the shorter distances.

"The 50m freestyle; I know my coach doesn't think it's the event for me but at this point in swimming I just want to have fun and get less tired.”