arrest on suspicion of intent to supply firearms

[tinkertatt]

my friend has been arrested on suspicion of intent to supply firearms, but as yet no evidence has been shown to him.the police say they have a tape recording of a conversation he had with another person who has also been arrested.when do they have to let him listen to this or let his solicitor hear it?is there a time limit at all?he has been denied bail & is on remand