Markus said he walked past the X Factor judge, but claims Simon completely ignored him. Oh dear... Maybe the sun was just in Simon's eyes?!
Markus told the Daily Mirror 3am: "I walked past Simon in Barbados and he completely blanked me like he didn't recognise me."
Markus, whose solo album Fire is due out on 16 october, also revealed that he actually considered auditioning for the ITV talent show after the boy band split in 2012.
"There were people waiting with contracts but it's not what I wanted to do," he said. "At one point, I was thinking, 'Should I go in for The X Factor as a solo artist?' I would have had to dress up and put a mask on but if they didn't know my voice after Westlife..."
Markus has recently premiered 'Butterfly', the second single from his album, following on from 'Love Is A Drug'.
Talking about his solo career, Markus said last month: "You might think someone who's had a 15-year career in music would think they've done it all. But I feel there's so much I want to do that I haven't done yet.
"That idea makes me feel as young as I did when I was starting out in Westlife. I'm really driven. I'm excited. And I'm ready to stand up and take charge."
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