TOKYO A global fund to tackle diseases such as HIV/AIDS, malaria and tuberculosis will be unveiled on Friday at a meeting of Group of Eight leaders, with contributions already nearing $1 billion, Japanese officials said on Wednesday.

The fund was launched last month by United Nations Secretary General Kofi Annan, who said between $7 billion and $10 billion would be needed to tackle effectively he three diseases that are rampant in many of the world's poorest countries.

The fund will be on the agenda for G8 leaders when they meet this week in Genoa for discussions including how to help developing countries, including debt relief and education.

Commitment to the health fund has already reached $985 million, including $200 million apiece from the United States, Japan and Britain, as well as $100 million from Microsoft Corp Chairman Bill Gates's charity foundation and millions from developing countries themselves, Reuters quoted Japanese officials as saying.

"What is remarkable here is that not only the developed nations and foundations but African countries themselves have put money into the fund," Kaoru Ishikawa, deputy director general of the Japanese Foreign Ministry's Economic Affairs Department, told reporters.

Ishikawa said $700 million of that has already been disbursed and Japan's $200 million contribution to the global health fund was in addition to that.

The fund will be used to procure drugs and medical equipment but a big emphasis is also placed on prevention.

"Among the three issues -- prevention, treatment and care -- we have to focus on prevention the most," Ishikawa said.