Katy Perry and John Meyer are so back on!

The on-an-off music pair were spotted holding hands and cuddled up to each other at 'Girls' actress, Allison Williams' wedding on Saturday, September 19.

Both reportedly came separately but they clearly couldn't keep their hands and eyes off each other during the lavish Wyoming ceremony.

"They are definitely back together. John and Katy looked happy. They held hands and sat next to each other during the wedding ceremony," a source at the wedding tells People.com

Kat, who also serenaded the couple and crowd with some of her hits, sported a long petal patterned gown while her beau looked dapper in a black suit, white shirt and dark tie.

The music couple have broken up twice in 2015 alone: The couple split in March after a brief reunion in January and reunited in July . But split again in August before been spotted together again at this September wedding.

Do you think Katy Perry and John Meyer should tie the knot

Enjoy a video of Katy Perry below: