Clifford Chance (CC) has selected seven more charities to provide client-level pro bono support to, three of which will receive a total of £345,000 from the firm over the next three years.

The non-governmental organisations (NGOs) joining the initiative are international development charity A4ID, affordable housing NGO Habitat for Humanity, non-profit writers' association PEN International, African Prisons Project, Anti-Slavery International, Institute for Human Rights and Business (IHRB) and Save the Children.

They join five charities chosen last year, which include human rights charities Fair Trials International (FTI) and Human Rights Watch.

The 12 charities in the scheme receive support from lawyers and support staff as a fee-paying client would, with each NGO partnership led by a dedicated relationship partner. They are chosen according to criteria including the potential to engage CC's clients and their international presence.

CC pro bono partner Roger Leese said: "We aim to take a similar approach to these partnerships as we do with our fee-paying clients, ensuring them of our top-notch quality and breadth of service at all times."

Human Rights Watch, FTI and IHRB are being granted access to funding, with the former set to receive £55,000 this year as part of a three-year package totalling £165,000. FTI and IHRB will both receive £30,000 this year as part of a three-year package amounting to £90,000.

Last year the firm granted funding to refugee rights group Asylum Access and education non-profit Room to Read, with both charities receiving three-year packages respectively totalling £200,000 and £103,000.

The firm has said that its lawyers and business staff have invested nearly 60,000 hours in pro bono and community work worth £19.2m during the 2012-13 financial year.

Related: CC picks five NGOs for client-level pro bono backing.