By Emma Jane Kirby BBC correspondent in Geneva

The World Health Organization and Unicef are to launch a major immunisation campaign aimed at tackling a polio epidemic sweeping northern India.

We are at risk of seeing polio spread in areas where it's already been brought under control Dr Daniel Tarantola WHO

Over 1.3 million volunteers and health workers will go on a house-to-house mission, in a bid to vaccinate every child under five years of age.

Africa and Asia are the only continents which still report cases of polio.

The WHO warns that further funding is needed if its to succeed in its target of freeing the whole world from the disease by 2005.

Winning the war

Last year was the target year set by the WHO to stop polio-virus transmission globally, but in 2002 India reported more than 1,500 new cases of the disease.

Countries where polio is endemic

India Pakistan Nigeria Afghanistan Niger Somalia Egypt Angola Ethiopia Sudan

To combat what is now the largest polio epidemic in recent history, the UN health body and Unicef, the UN Children's Fund, will launch their biggest-ever immunisation campaign.

In all, 165 million Indian children will be targeted throughout this year and next.

Although there is no cure for polio, it can be prevented.

The UN agencies urged the international community to help them raise further funding for vaccination programmes.

Polio eradication is facing a funding gap of $275m worldwide and the immunisation programme for India is itself short of $100m.

The WHO insisted it was winning the war against the disease, however, and its goal to eradicate polio globally by 2005 remains within reach.