The prince celebrated his 31st birthday with his friends in a private room in a West London pub on Tuesday night (15.09.15), and was joined for the occasion by the 26-year-old actress.
A source revealed: ''The party started at about 8pm and went on until about 1.30am. There was even a birthday cake with fireworks coming out of it.
''Cressida turned up with a female friend about 9.30pm and stood at the bar apparently waiting for Harry.
''She was there with him and his inner circle for the rest of the night, which shows how close they are.
''It's very early days and Harry is weighing up his options, but there are obviously still feelings there for Cressida.''
Harry and Cressida left the bash at different times, but the prince reportedly invited Cressida to join him at Kensington Palace for an after-party.
However, a palace source denied speculation he'd invited her back to his private quarters.
The insider shared: ''Harry wants to try and give his relationship with Cressida one more chance.''
Harry was recently linked to another of his ex-girlfriends, Chelsy Davy, but a relationship with Cressida was described as ''much more practical and realistic''.
The source told The Sun newspaper: ''Obviously it's not going to be nice for Chelsy to see, but she remains on good terms with Harry.
''There are definitely feelings there too but a relationship with Cressida feels much more practical and realistic.
''Chelsy has never wanted a royal life.''
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