The throwaway remark came at the end of his acceptance speech for Best Male Solo Artist at the Brit awards.
The speech was given by supermodel Kate Moss because Bowie, 67, chose to stay at home in New York rather than attend the event in London to pick up his first Brit for 18 years.
She said: "Good evening ladies and gentleman, David has asked me to say this. I'm completely delighted to have a Brit for being the best male - but I am, aren't I Kate? I think it's a great way to end the day. Thank you very, very much and Scotland stay with us."
Noel Gallagher who announced Bowie as the winner said: "You maniacs didn't think David Bowie was actually going to be here? David Bowie's too cool for that - he doesn't do this s***.
Bowie's wasn't a political address, but the comment will nonetheless will be seized on by unionists as the independence debate ratchets up further.
Only 24 hours earlier, Glasgow-born award-winning designer Christopher Kane had also endorsed a United Kingdom at a style awards ceremony.
Moss arrived secretly, avoiding the red carpet, to surprise guests at the Brits. And when she arrived on stage the 40-year-old model was wearing wore one of his Ziggy Stardust outfits which Bowie himself made famous at one of the most celebrated stages of his career.
London-born Bowie originally donned the leotard-style garment while appearing at London's Rainbow Theatre in Finsbury Park on August 19, 1972. The costume, called 'Woodland Creatures' but popularly known as his 'rabbit costume' was designed by Kansai Yamamoto.
Moss and Bowie have had an association for a number of years, with the model interviewing Bowie for Q magazine more than a decade ago, also posing for a cover shoot together.
With tonight's win he has become the oldest star to be awarded a Brit, succeeding Sir Tom Jones who was 62 when he picked up his outstanding contribution prize.
Bowie returned to the music world early last year surprising his fans by coming out of what had appeared to be retirement, releasing his album The Next Day after a ten-year recording silence.