Microsoft's Bill Gates met with Alibaba Group Holding Ltd's Jack Ma in Beijing, June 18, 2014. [Photo/Bill Gates' Twitter account]

Microsoft's Bill Gates met with Alibaba Group Holding Ltd's Jack Ma to discuss charity work in a private dinner in Beijing, according to a post by the world's richest man on Twitter on Wednesday.

"Got to meet with Alibaba's Jack Ma Yun in Beijing to talk philanthropy - great conversation," Gates said on his Twitter feed. 

Ma, the chairman of China's e-commerce conglomerate, threw a dinner for Gates on Tuesday night in Beijing, according to a Weibo post by property developer Ren Zhiqiang, who was also invited.

Several of China's philanthropists and business leaders were at Ma's dinner as well. Alibaba's official Weibo account said the dinner was not an official meeting. Charity work in China and the world was discussed at the event, said Alibaba Group's post on Wednesday.

Based on the photos posted by Ren Zhiqiang, Niu Gensheng, founder of China dairy giant Mengniu and Ma Weihua, former president of China Merchants Bank, were among those who attended the dinner. 

Jack Ma and Joe Tsai, a co-founder of Alibaba Group, said in April that they will donate about 2 percent of Alibaba's equity to set up personal charitable trusts. 

Since Alibaba Group is expected to launch one of the largest initial public offerings in the US, which could value the company at $150 billion, Ma and Tsai's trusts will be worth roughly $3 billion - by far the largest endowment of its kind in China.

According to a previous media release, Ma and Tsai's twin trusts will focus on improving China's environment, health care, education and culture.