John Mayer and Katy Perry, who have been in an on and off relationship, are reportedly back together again.

They were spotted holding hands at actress Allison Williams' wedding over the weekend.

"John and Katy looked happy. They held hands and sat next to each other during the wedding ceremony," a source told people.com.

The duo split up twice earlier this year, first calling it quits in March 2015 and again in July.

The duo, who split in February of 2014, fuelled reconciliation rumours when they stepped out for a double date with Williams and her then-fiance Ricky Van Veen at a hotel named Chateau Marmont in January.

"They are so in love. They missed each other," a source close to Perry said at the time.