Kelly Osbourne has said Adam Lambert is the "hottest date on earth" after going to a book launch together.

The two celebrities are friends and it seems the duo spent some time together last night (January 13).

Osbourne tweeted that she attended a book launch of fashion man George Kotsiopoulos with the 'Trespassing' singer.

However, it was her glowing praise of Lambert's good looks that raised some eyebrows, with the Fashion Police lady saying:

"I have the hottest date on earth tonight! @adamlambert is taking me to @GeorgeKotsi book launch! #ImALuckyLady."

Osbourne meanwhile is a free lady after splitting from former fiancé Matthew Mosshart last week.

She later admitted that there was no "dramatic story" behind the break-up, with the couple just drifting apart.