Katy Perry, Robert Pattinson Crash Calif. Wedding: Is Katy Perry Dating John Mayer?

Days after sources claimed singer Katy Perry was the reason behind the highly publicized split of “Twilight” co-stars Robert Pattinson and Kristen Stewart, Hollywood’s new rumored “it” couple was spotted out together again this weekend.

While Pattinson, 27, and Perry, 28, have been reported canoodling at private dinners and sneaking off in an SUV after the Met Gala in New York earlier this month, the latest sighting was a very public one. According to People magazine, the two were seen crashing a wedding rehearsal at San Ysidro Ranch in Montecito, Calif., Saturday.

Close family members of the wedding couple, 26-year-old John Ricotta and 23-year-old Tanya Mayer, said the stars were not invited but were just watching from a nearby courtyard -- to the delight of the bride and groom-to-be.

“It was extra exciting for Tanya and John,” said the source. “[Perry and Pattinson] were just sitting quietly and talking and we were on the lawn nearby. We respected their privacy.”

But while some fans claim the wedding date means Perry and Pattinson are now romantically linked, conflicting reports say the “I Kissed a Girl” singer is back with her former flame, fellow singer John Mayer.

According to US Weekly, the former couple reunited at a barbecue celebration at Perry’s Hollywood Hills mansion on May 27. One partygoer said their interactions were “definitely friendly,” while another claimed the duo seemed to be on-again after two previous breakups.

“They seem to be back together — or back together-ish. They were very flirty and having a really good time. They have good chemistry,” said a source.

It was previously reported that Pattinson was merely taking a break from his 23-year-old “Twilight” lover after having a disagreement over “priorities.” According to sources, the duo is expected to reunite after a period of separation but are currently living together in their shared California home for the sake of their pets.