He is launching a campaign to turn her into a superstar and is taking her to Los Angeles to wow industry gurus, according to reports.

A source told the Daily Star: "Simon knows that if Leona is going to become a world superstar she needs to crack America. So he has organised a small concert where Leona will perform a showcase of songs for a load of bigwigs.

"He thinks she’ll knock their socks off and they’ll be desperate to work with her. If he gets them on side, Leona’s future looks rosy."

Yesterday Leona was knocked off her No 1 place in the UK Singles Chart by Beirut-born Mika’s track Grace Kelly.

She had spent four weeks at the top with her single A Moment Like This.

Leona makes it four in a row - Jan 15 2007
X Factor winner Leona Lewis is still riding high at the top of the charts with her debut single A Moment Like This.

The reality television show winner has made it four weeks at the top after winning the show back in December.

Eric Prydz was also a non-mover, still at No 2 with Proper Education ahead of new entry Mika with Grace Kelly at No 3.

The second highest new entry was Just Jack with Starz In Their Eyes, pushing Take That’s Patience down into the No 5 slot.

JoJo rocketed up from 22 to No 6 after nine weeks in the chart with her track Too Little Too Late.

Booty Luv were at No 7 with Boogie 2Nite, ahead of Akon featuring Eminem with Smack That, Sharam with Patt (Party All The Time) and Cascada at No 10 with Truly Madly Deeply.

Rehab singer Amy Winehouse climbed to the top of the album chart with her latest offering Back To Black.

She rose from the No 2 spot which was then taken by James Morrison’s Undiscovered, up three places from No 5.

Snow Patrol’s Eyes Open was a non-mover at No 3 and Take That’s Beautiful World fell from the top slot to No 4.

The Fratellies rose one place, up to No 5 with their album Costello Music.

Kylie Minogue’s Showgirl - Homecoming Live album was the highest new entry at No 7.

Leona holds on to top slot - Jan 8 2007
X Factor winner Leona Lewis has held on to No 1 in the revamped singles charts.

The 21-year-old’s debut single A Moment Like This took the top position for the second week in a row.

Eric Prydz Vs Floyd’s Proper Education jumped to the No 2 spot, while Take That’s comeback Patience slipped to third place.

New chart rules which came into force last week mean old favourites are making a surprise comeback.

Hailed as the biggest shake-up in the charts since its inception in 1952, the changes mean any song available as an internet download is eligible for the chart.

So Snow Patrol’s Chasing Cars is at this week’s No 9, while Gnarls Barkley’s Crazy is at 30.

Mad World, the 2003 Christmas No 1 from the Donnie Darko soundtrack was tipped to make a return but failed to reappear.

"Under the new rules, anything and everything is eligible," said HMV spokesman Gennaro Castaldo.

"January is always the quietest month for singles sales so these older songs are benefiting from that. But old releases are likely to feature heavily from now on."

The shake-up also raises the possibility of the Beatles staging a chart comeback, following rumours that EMI is negotiating to release the band’s back catalogue as downloads for the first time.