Tories would use the £200 million which the NHS stands to save from their decision not to go ahead with Labour's planned 1% rise in National Insurance to pay for drugs which have been rejected by the National Institute for Clinical Excellence (Nice), said the Conservative leader.

From 2011, the money would be put into a new Cancer Drugs Fund to pay for any cancer medicine licensed since 2005 if doctors say their patients need it, even if it has not got Nice approval.

And Conservatives say that, by 2014, they will introduce reforms to ensure that effective treatments are made available through the NHS, with drug providers paid according to the value of their new treatments.

Mr Cameron said: "We have a problem in Britain that other European countries are doing better than us at giving people longer, happier lives with cancer than we are.

"So we want to get more drugs to people more quickly and in the UK today there are some people, thousands of people, who want a certain cancer drug whose doctors tell them they should have a certain cancer drug who don't get it. 

"So we are saying because we are not going ahead with this National Insurance increase, that will save the NHS money and we are going to put that money into a cancer drugs fund.

"So these thousands of people who want a drug whose doctors would like them to have a drug can get that drug."