The 'What Makes You Beautiful' singer revealed to Ryan Seacrest that he has been in touch with Lovato and is waiting to see "what's going to happen".
"We've spoken alright, yeah," he teased during an appearance on KIIS-FM. "So, I got in contact with her.
"She's really nice. I don't know what's going to happen."
Speaking to Digital Spy recently, Horan confessed that he has seen "a bit too much" of some of his female fans.
"You can see girls getting too excited and they start crying or worse," he said. "In a lot of these countries they don't get a lot of gigs to go to, so when they get to see their favourite artist they take full advantage of it.
"Obviously the excitement builds up too much for some on the night and they get a bit... crazy."
Horan's father previously claimed that the 18-year-old is in love with a girl from his local Irish town and admitted that the star is probably not a virgin.
Lovato briefly dated another teen popstar, Joe Jonas, in 2010.