David Foster and Katharine McPhee seal romance rumors with a kiss

Music producer David Foster and singer/actress Katharine Mcphee have been caught on camera sealing their rumored romance with a kiss.

The Smash star, 33, has been linked to the 68-year-old composer and songwriter since earlier this year (17), and in September his daughter, comedienne and actress Erin Foster, fueled the relationship speculation by posting a picture of Katharine and her dad on Instagram and captioning it: "Excited about my new step mom."

Katharine has repeatedly brushed off the romance claims, and recently insisted Erin's post was part of a big joke, but she appeared to be more than just friends with David on Thursday (30Nov17), when the pair was photographed locking lips as they arrived for a lunch date in Beverly Hills, California.

In the images, published on TMZ.com, David is pictured wearing a black suit jacket over a white shirt and jeans, while Katharine opted for a more relaxed look in a black top, blue jeans, and a long black coat, as they puckered up for a kiss.

The photos emerge just weeks after Katharine attempted to clear up the nature of their relationship in an interview with Health magazine.

"(David and I) are very close friends, and we've been friends for a long time," she said. "I'm really, really fond of him, and I think he's an incredible person. I've known him since I was 21 years old, you know? He produced my first single. So he's been really good to me. People can say whatever they want."

Katharine went on to claim she has been "pretty single" since splitting from her Scorpion co-star Elyes Gabel last year (16).

She was previously married to Nick Cokas. They divorced in February, 2016.

David has been single since splitting from his fourth wife, Dutch model Yolanda Hadid, in 2015. The former couple's divorce was finalized in May (17).