Hundreds of people have fallen victim to traffickers in Northern Ireland, First Minister Peter Robinson said.
Many were exploited in a modern-day version of the slavery of previous centuries, the DUP leader added.
His party is supporting an assembly Bill toughening measures surrounding prostitution. Part of it faces opposition from some experts and senior MLAs who fear driving the trade underground or threatening the safety of women.
Mr Robinson said: “There are hundreds of people being exploited here in Northern Ireland, people being dehumanised.
“It is essential that we do what they did back in the time of Wilberforce, where it was recognised that there should not be slavery.”
William Wilberforce was an English MP who led the movement to abolish the slave trade in the early 1800s.
DUP Fermanagh and South Tyrone MLA Lord Maurice Morrow is piloting Stormont legislation dealing with prostitution and trafficking.
He and the First Minister attended a Stormont event on trafficking today.
Justice minister David Ford believes criminalising paying for sex could threaten the safety of prostitutes.
The clause in Lord Morrow’s draft law would be difficult to enforce and the police do not support it, the minister has added.
If a prosecution was undertaken, the woman risked being intimidated by the purchaser of sex for going to the authorities.
Lord Morrow has insisted a new prostitution law is vital to effectively tackle human trafficking, arguing that outlawing payment would simplify the law and make it easier to secure convictions that send a clear message to offenders.
Since April this year, at least 13 potential human trafficking victims have been referred for specialist support.
Often they are vulnerable, lured by traffickers with false promises of paid employment, intimidated and having little idea how to seek help.
Lord Morrow has argued that his proposed legislation seeks to reduce demand for sexual services, a major driver for trafficking.
Mr Ford also expressed concern that part of the draft law setting a two-year minimum sentence for trafficking and slavery offences could fetter the discretion of judges, who he said were best placed to consider the broad scope of circumstances in any particular case.
According to Lord Morrow, under the draft law a child victim would not be punished for crimes which were the direct consequence of trafficking. A child trafficking guardian would be established to speak up for victims.
The peer’s proposed legislation, the Human Trafficking and Exploitation Bill, contains 19 clauses updating Northern Ireland’s laws on prostitution and trafficking.
It will be considered by an Assembly committee.