Former X factor judge and N-Dubz star Tulisa told an undercover reporter she could get hold of "white sweets" in an apparent reference to cocaine, a court heard.
The singer "did not negotiate the price or amount" but "did all she could to make a supply of cocaine happen," prosecutor Tim Cray said.
He added Tulisa's role in the deal at London's Dorchester Hotel in May last year was "instrumental."
The trial at Southwark Crown Court continues.
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