The deal will reduce the cost of Aids drugs in developing countries

The Clinton Foundation's agreement will cut the cost of what are known as second line anti-retrovirals by 25-50%.

Second line drugs are used when cheaper and earlier forms of treatment fail.

The new generic drugs will be made available to people with HIV/Aids in more than 60 countries in Africa, Asia, Latin America and the Caribbean.

Mr Clinton said seven million people in those countries were in need of treatment for HIV/Aids, but could not afford it.

This drug represents the best chance that science has to offer and we're announcing this price to help national governments plan for the use of the product in the future

Bill Clinton

He said that the pact, made in partnership with international drug purchase facility Unitaid, would sharply reduce the costs of treating people living with HIV/Aids in many developing countries.

He said the two companies had worked with the foundation to reduce production costs, partly through the use of cheaper materials and partly through improved technique.

'Best hope'

"Less than a year after the launch of an Aids treatment that is one pill, once a day, which is so much easier for people to take, we're announcing a price of less than a dollar a day for developing countries," Mr Clinton said in a speech at the Clinton Foundation's offices in New York.

Mr Clinton's foundation supplies medicine to 750,000 people

The lower cost, once-daily pill combines the drugs tenofovir, lamivudine and efavirenz.

"This drug represents the best chance that science has to offer and we're announcing this price to help national governments plan for the use of the product in the future," Mr Clinton said.

Mr Clinton was joined by the health ministers of Thailand and Kenya, the chairman of Matrix and France's ambassador to the US as he made the announcement.

'Sky-high costs'

A spokesman from the Global Fund to Fight Aids, TB and Malaria, Kingsley Moghelu, told the BBC that the deal will make a big difference in the lives of people requiring these drugs:

It takes the fight against Aids really where it is most important

Global Fund to Fight Aids, TB and Malaria spokesman Kingsley Moghelu

"Second-line therapies are atrociously expensive. They cost 10 times more than first-line therapies.

"Whether or not you can afford to buy the medicines, if you need those medicines, is often the difference between life and death."

Since leaving office in 2001, Bill Clinton has used the foundation that carries his name to tackle the global Aids epidemic.

Some 750,000 people are currently receiving drug treatments for Aids through the foundation.

The disease now affects some 40 million people globally, and has killed 25 million since it was first identified in the 1970s.