Simon Cowell is "getting serious" with make-up artist Mezhgan Hussainy.
The 50-year-old music mogul was spotted on a date at exclusive London restaurant Mr Chow with the 36-year-old beauty, and the pair are believed to be ready to go public with the romance.
A source said: "Simon is ready to let everyone know. Things between them are moving along very nicely indeed.
"Their relationship has been conducted under a cloak of secrecy but the situation has now changed."
A diner at the eatery added: "It was clear there was real chemistry between them. He seemed smitten and she likewise."
Mezhgan, who was born in Afghanistan before moving to the US in the early 80s, joins a long list of beauties who have dated Simon, including model Terri Seymour and 'So Macho' singer Sinitta.
The source added: "Simon is clearly very enamored with Mezhgan - and it's little wonder why. She is absolutely stunning, not to mention incredibly intelligent and cultured."