The "Thinking Out Loud" hitmaker, 23, who played matchmaker for the "Friends" star and Snow Patrol rocker Johnny McDaid, is expected to perform the service when the pair tie the knot, reported Femalefirst.
"They both agree it would be tons of fun as well as extremely fitting if Ed's the one to join them in holy matrimony.
"He had already agreed to perform a couple of ballads after they exchange vows, so it seemed logical to him that he should get them hitched too," a source said.