The latest software update has added this feature. You can update by clicking here
When the alarm sounds if you press any of the pre-set buttons 1-5 this will snooze the radio. The snooze is set to 8 minutes by default.
If you would like to cancel the Snooze this can be done by pressing any of the keys on the back row (Source, left, select, right and menu).
You can adjust the default snooze time by selecting Menu> Clock> Snooze and you can select between 5-59 minutes.