The Twilight actor was spotted at a New York City nightclub with the unidentified blonde, and photographs obtained by TMZ appeared to show him flirting with her.
The low-resolution images were reportedly taken on Saturday night (October 6) at the Electric Room in Manhattan.
Sources inside the venue claimed that Pattinson was with the woman for hours, at one point putting his arm around her.
It has been reported that Pattinson and Stewart have reconciled, following the revelation that she had cheated on him earlier this year with Snow White and The Huntsman director Rupert Sanders, who is married to model Liberty Ross.
Despite rumours of a reconciliation between Pattinson and Stewart, an insider has claimed that they will work separately to promote the final Twilight movie Breaking Dawn - Part 2, visiting Australia and Japan respectively.
Their Twilight co-star Taylor Lautner is expected to head to Brazil at the same time.
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