The glamorous couple were both in attendance at UNICEF's 12th annual Snowflake Ball in New York City but decided not to pose together for photos.
Katy, 32, looked gorgeous (as per usual) in an ethereal, flowing gown by Marchesa, while Orlando, 39, sported platinum blonde locks rather than his usual dark hair.
Katy and Orlando are both very involved in UNICEF's work. As a Goodwill Ambassador, Katy visited disadvantaged children in Vietnam earlier this year, while fellow Goodwill Ambassador Orlando travelled to Ukraine in May to raise awareness for children affected by the conflict.
The couple were hit by split rumours earlier this month, which claimed they'd ended their ten-month relationship. But Katy was quick to rubbish the claims via Instagram, sharing a video of her family's Thanksgiving celebration where Orlando was in attendance.
Now the rumours have gone to the opposite extreme with speculation of an engagement! We can't keep up!
According to Entertainment Tonight, popstar Katy was pictured recently out in New York with a sparkling diamond firmly on display on her engagement ring finger.
However, there was no ring in sight at the Snowflake Ball, suggesting it was simply a piece of jewellery she chose to wear on that finger, rather than a sign of engagement.
A source told People back in August they wouldn't be surprised if Katy and Orlando did announce an engagement eventually, but it hadn't happened yet.
The insider alleged: "[They] not engaged yet, but seem to be heading that way. He would love to settle down with Katy and have more kids."
Orlando is dad to son Flynn, five, with ex-wife, model Miranda Kerr.
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