The pop hunks were hanging out in Los Angeles together when they were caught on camera with the suspicious glass object on a table nearby.
Niall, 21, stares blankly into the distance in the footage while 21-year-old Bieber sings along to his friend Cody Simpson’s guitar.
The yellow pipe, commonly used to smoke cannabis, crystal meth and crack, can be clearly seen on the coffee table along with a lighter, bottles of water and the TV remote.
Other items on the grubby-looking table are too small to identify in the 10-second clip from Australian singer Cody’s Snapchat account.
Last night the images sparked rumours the teen idols were using hard drugs - although there is no suggestion that this is the case.
One horrified Directioner wrote on Twitter: “I trusted you Niall how could you hurt me like this? I’m literally paying for his drugs!!!”
Others accused wild child Justin Bieber of dragging Irishman Niall into his party lifestyle.
One wrote: “Don’t start smoking and doing drugs now because you’re part of Justin’s squad. PLEASE STAY INNOCENT.”
Another added: “Niall is hanging out with Justin. Please don’t get into drugs Niall.”
The normally squeaky-clean star had earlier met up with Liverpool legend Steven Gerrard, 35, for a round of golf to celebrate the ex-England captain’s goal-scoring debut for LA Galaxy. He posed for a picture at the exclusive Hillcrest Country Club before meeting up with the other two boys.
Bieber got to know 18-year-old Cody when they worked on single Home To Mama together - a tribute to the Aussie’s supermodel ex Gigi Hadid, 20.
Posted by Adebayo A J