A legislative bid to ban paying for sex in Northern Ireland has passed its final stage in the Stormont Assembly.

The region will become the first part of the UK to introduce such a clampdown when the Bill receives the formality of royal assent.

The law change, championed by Democratic Unionist Assembly Member Lord Morrow, has been hailed by Christian groups but denounced by prostitutes' representatives.

Paid-for consensual sex is legal in Northern Ireland although activities such as kerb crawling, brothel keeping and pimping are against the law.

The ban will see the region implement a prohibition similar to the model in Sweden.

The proposal to outlaw purchasing sex is among a number of clauses in Lord Morrow's Private Member's Bill aimed at amending Northern Ireland's laws on trafficking and prostitution.

As the Bill passed its final Assembly stage, Lord Morrow thanked those who supported him.

"Northern Ireland is now at the forefront of efforts to combat human trafficking and I am very grateful to all those MLAs who ensured there was cross-party support for the Bill," he said.

"To those who were still to be convinced I hope that time and robust implementation of the legislation will help change their minds.

"I have been driven on throughout this process by the support of the public and the desire to make a difference in the lives of some of the most vulnerable people in our society."

The fate of the Bill's contentious clause six, proposing the ban on purchasing sex, was uncertain at the outset of a crunch debate in October, with Sinn Fein's decision to back the prohibition with the DUP proving crucial.

DUP First Minister Peter Robinson said: "This is without a doubt one of the most far-reaching and significant pieces of legislation to pass the Northern Ireland Assembly.

"Maurice Morrow has been successful in building a coalition of support for this legislation which will undoubtedly save lives in Northern Ireland.

"Over the course of the last three years he has had to overcome significant hurdles on the way to final stage today, but he persisted and has succeeded. It is a model of how one individual MLA can, through hard work and devotion to a cause, change things for the better."