|Harry Styles and a koala|
He is quoted by the Daily Mirror newspaper as saying: "We're young lads, and you can date older women when you're older.
"But when you're older, you can't really get away with dating 18 or 19 year olds.
"We have been asked that before, I think it was around the time of Harry's little fling. In particular, how old's too old? For me, probably 23 or 24."
While Louis and Liam - who are dating student Eleanor Calder and dancer Danielle Peazer respectively - are enjoying their ever-increasing fame, the pair are determined not to give up their girlfriends as a result.
A friend recently said: "There's been a lot of talk about the 1D boys being banned from having girlfriends.
It's better as it makes them seem more attainable - particularly with their new army of female fans in the US.
"But there's absolutely no way Liam and Louis will give up Danielle and Eleanor. They don't see why their personal lives should suffer."