Katy and Kristen friends again

Katy Perry appears to have mended her friendship with Kristen Stewart.

The 'Part of Me' singer - who reportedly supported close pal Robert Pattinson and encouraged him to move on after the 'Twilight Saga' hunk was left devastated when Kristen cheated on him with married director Rupert Sanders - was spotted celebrating her birthday with the 'Snow White And The Huntsman' actress on Friday night.