Japan's Prime Minister Shinzo Abe told African leaders on Saturday that his country will commit $30 billion in public and private support for infrastructure development on the continent.

Resource-poor Japan has long been interested in tapping Africa's vast natural resources, even more so since dependence on oil and natural gas imports jumped after the 2011 Fukushima nuclear disaster shut almost all of Japan's nuclear reactors.

Abe, in the Kenyan capital Nairobi to attend the sixth Tokyo International Conference on African Development (TICAD), said the package would be spread over three years from this year and include $10 billion for infrastructure projects on the continent, to be executed through cooperation with the African Development Bank.

"When combined with investment from the private sector, I expect that the total will amount to $30 billion. This is an investment that has faith in Africa's future, an investment for Japan and Africa to grow together," he told a gathering of at least 34 heads of state and government from across Africa.

The $30 billion announced on Saturday is in addition to $32 billion that Japan pledged to Africa over a five-year period at the last TICAD meeting in 2013. Abe said 67 percent of that had already been put to use in various projects.

"Today's new pledges will enhance and further expand upon those launched three years ago. The motive is quality and enhancement," he said.

Japan's overall direct investment in Africa totaled $1.24 billion in 2015, down from about $1.5 billion a year earlier, according to the Japan External Trade Organization, which does not provide a breakdown of sectors.

    In comparison, rival China made a single investment of $2 billion in oil-rich Equatorial Guinea in the month of April, 2015, alone.

Abe said the new pledge will also go towards improving labor productivity and healthcare.