A PLEDGE to eradicate modern slavery around the world by 2020 was signed in Rome on Tuesday by global faith leaders, including the Archbishop of Canterbury.

The Joint Declaration of Religious Leaders Against Modern Slavery was signed days after it was suggested that the number of victims in the UK could be as high as 13,000 a year. It states that the signatories will "do all in our power, within our faith communities and beyond, to work together for the freedom of all those who are enslaved and trafficked so that their future may be restored".

It follows the launch of the Global Freedom Network, an interfaith anti-slavery movement, in March (News, 21 March), expanding it to a wider circle of faiths. The 12 signatories include Pope Francis, Archbishop Welby, the Hindu spiritual leader Her Holiness Mata Amritanandamayi (known as "Amma"), the Buddhist leader Zen Master Thich Nhat Hanh, the director of the American Jewish Committee's Department of Interreligious Affairs, Rabbi David Rosen, the Ecumenical Patriarch, Bartholomew I, and four Muslim leaders, including the Grand Imam of Al-Azhar, Mohamed Ahmed El-Tayeb, and the Grand Ayatollah Mohammad Taqi al-Modarresi.

Speaking at the signing, Archbishop Welby said that the leaders had "joined together for the liberation of the most vulnerable in our world". He spoke of the "unimaginable" suffering of more than 30 million people "oppressed in some form of slavery - trafficking, forced labour and prostitution, the trade in human organs, and many more outrages". The problem was "acute and growing, facilitated by a globalised economy that is too easily without moral or conscience".

Faith leaders had a responsibility to make sure that all worshippers knew about modern slavery and were committed to preventing it, choosing where to invest, welcoming victims into their communities, and pressing governments to pass effective legislation.

On Saturday, the Home Office published research suggesting that there were between 10,000 and 13,000 victims of modern slavery in the UK last year. It also launched a Modern Slavery Strategy. This refers to a national action plan for police forces, the publication of successful convictions, including details of sentences, and work with the private sector to "prevent facilitation within the legitimate economy". There are plans to improve reparations, "to ensure more money recovered from convicted traffickers and slavedrivers goes to victims". The strategy speaks of working with faith bodies, including the Church of England and Anglican Communion.

The strategy will sit alongside the Modern Slavery Bill, which is currently in Committee Stage in the House of Lords. The Bishop of Derby, Dr Alistair Redfern, spoke on Monday in support of an amendment to make it an offence to pay for sexual services. It was a "myth", he said, that "prostitution can be simply a marketable form of employment. . . It is evident that almost everybody who I have come across, or who colleagues work with, are pathetic, abused, and often drug-centred young women."