China is not putting any pressure on self-ruled Taiwan's last diplomatic ally in Africa, the Kingdom of eSwatini, to switch to Beijing, but believes it is just a matter of time before that happens, a senior Chinese diplomat said on Saturday.

China has become increasingly vocal about its desire to win away the country, formerly known as Swaziland, from Taiwan, even as the eSwatini government has denounced Beijing for playing "mind games" and says it has no desire to ditch Taipei.

eSwatini will be the only African country not represented at a major summit between China and the continent opening in Beijing on Monday, where President Xi Jinping is likely to offer new loans and aid for Africa.