Harriet Harman has clashed with unions attempting to legalise prostitution, insisting that “buying someone for sex is abuse”.

Labour’s former deputy leader spoke out ahead of a controversial vote at the Trades Union Congress conference tomorrow in Brighton to legalise prostitution.

The GMB and Aslef unions want to see the decriminalisation of sex work, saying it would improve safety for the thousands of men and women who sell their bodies.

They want the “New Zealand model” where prostitutes have full legal protection.

But writing on Twitter, Ms Harman said: “Noooooo! So wrong #tuc protect the vulnerable & exploited! Don't legitimise their exploitation.

“Buying someone for sex is abuse. Should be a crime.”