The pledge comes on top of a 2015 promise to provide African countries with $60 billion in funding that Xi said had either been delivered or arranged.
China planned to exempt some African countries from interest-free loans due by the end of the year, Xi said, adding that the relief would be granted to the continent's poorest and most heavily indebted countries.
He did not say which countries would have their debt absolved, but the move appeared to be the latest effort by Beijing to deflect concerns about debt levels on the continent and the risks of "debt trap diplomacy".
Chinese Foreign Minister Wang Yi told his African counterparts Sunday that Xi will use the summit as an opportunity to outline a "specific vision on building a China-Africa community with a shared future, and announce proposals and measures.to strengthen China-Africa cooperation".
But critics say that, with many of its infrastructure projects, China is luring needy countries into "debt traps".
Xi said Belt and Road complies with global norms, and China "welcomes the participation of other capable and willing countries for mutually beneficial third-party cooperation". Chinese companies would also be encouraged to invest at least $10 billion in Africa over the next three years, state media reported. China will carry out 50 agricultural assistance programs, provide emergency humanitarian food aid amounting to 1 billion yuan (147 million USA dollars) to African countries affected by natural disasters, and send 500 senior agricultural experts to Africa.
"The Forum, in which the Chinese and African leaders will exchange in-depth views on the development of China-Africa relations and worldwide and regional issues of common concern, has President Cyril Ramaphosa of South Africa, as the African co-chair", Xiaoliang said.
Later, at the start of the Forum on China-Africa Cooperation (FOCAC), Xi announced $60 billion in funds for eight initiatives over the next three years, in areas ranging from industrial promotion, infrastructure construction and scholarships for young Africans.
He said China will launch an infrastructure initiative with Africa and will support those companies involved in infrastructure development in Africa.
"The seven or so special economic zones set up by Chinese actors in Africa have encountered a number of difficulties.so there is much scope for growth", Anthony said.
"China's investment in Africa comes with no political strings attached, " said Xi.
"China's cooperation with Africa is clearly targeted at the major bottlenecks to development", Xi said, in a possible preview of his speech to the summit later Monday.
He added that China values sincerity and trust in pursuit of partnership cooperation and has neither any attachments to the strength in the continent nor seek any gains while cooperating with Africa. It has since dipped and past year continued a slow recovery to $170 billion.
President Cyril Ramaphosa is visiting China for the China- Africa Cooperation Summit and so far his visit has been described as a positive move that could result in job creation in South Africa.
Speaking earlier at a business forum, Xi said China had to be careful about where money was spent.
"Another perspective.is that those criticising China on debt give too little", said Kagame in an interview with the official Xinhua news agency.
"As it is, nearly all African countries have loans or grants from China, so it would make economic sense to repay in yuan", said MEFMI spokesperson Gladys Siwela-Jadagu.
Rather than exporting a mass of raw materials, as Africa has traditionally done with its Asian partners, importing natural resources from China could open an abundance of employment for African countries.
Analysts said China's pledges highlighted Africa's growing importance to Beijing as its trade war with Washington escalated. "Is China unfairly exploiting Africa like the others before it?"