The actress was pictured leaving a pub in Central London where Harry and his friends had been marking his big day earlier this week.
Of course, now the rumours have started that Harry and Cressida, 26, are thinking about giving their romance another go…
An insider told The Sun: "It's very early days and Harry is weighing up his options but there are obviously still feelings there for Cressida."
Cressida is thought to have split from actor boyfriend Edward Holcroft earlier this week, while Harry is currently single. The couple met in 2012 and dated until last year, and are thought to have remained friends, as evidenced by Cressida's appearance at Harry's birthday.
But just to confuse things, the party at a pub in Chelsea, West London, came amid rumours Harry could give his romance with ex-ex-girlfriend Chelsy Davy another go…
Harry and Chelsy dated from 2004 until 2011 and reportedly split because Chelsy didn't want to live the royal life and preferred going to uni and studying to be a lawyer, which she did.
A source told Us Weekly: They still have strong feelings for each other."
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