United Kingdom, Oct. 6 -- Robert De Niro owns 18 dogs.

That's according to fellow Hollywood actor Woody Harrelson, who was left shocked at the number of canines his Wag the Dog co-star has.

Speaking to Interview magazine, he said De Niro had "18 dogs" when he recently visited his house in New York.

The 65-year-old actor explained: "We went over to his house here in New York, and nine dogs came to the door.

"They're these little dogs, they get to do whatever they want."

Despite starring alongside him in 1997 political satire movie Wag the Dog, Woody didn't really think of 83-year-old De Niro as a dog person before his visit.

He added: "Thinking about Bob De Niro, you don't think of him inside of this world with a zillion dogs."

But ...