David Cameron has announced a £10m international youth citizen service scheme.

The scheme, which will be means-tested, will focus mainly on 18 to 22-year-olds, who will work on projects aimed at improving the lives of some of the poorest people in the world.

In the pilot year (2011/12) places will be offered to 1,000 young people and to 250 more experienced older people. An evaluation will determine how best to scale up the scheme to offer places to many more applicants.

The Department for International Development will work with specialist volunteering agencies to pilot the scheme in the first year, with first-year costs of up to £10m.

The experience will be designed to broaden horizons, develop new skills and foster self-reliance.

Young volunteers will work on social action projects for three-month periods, in some places alongside older volunteers on longer placements.

From 2013, International Citizen Service will seek to include graduates of the UK-based National Citizen Service  programme for 16-year-olds.

Announcing the scheme at Conservative Conference yesterday, the Prime Ministersaid: "Last century, America's Peace Corps inspired a generation of young people to act, and this century I want International Citizen Service to do the same thing."