After being sworn into office, Mr Lai invited China to engage in dialogue with Taiwan and urged Beijing to “jointly shoulder the important responsibility of regional stability”.
But the Chinese Communist Party, which claims Taiwan as its own territory despite never ruling there, has snubbed his attempts to talk.
The three-day security forum in Singapore has been dominated by the strategic rivalry between the United States and China and its impact on the Indo-Pacific region.
Adml Dong, who met with Lloyd Austin, the US defence secretary, for the first time face-to-face on Friday, said that more dialogue was necessary because of the differences between the two militaries.
“We have always been open to exchanges and co-operation, but this requires both sides to meet each other halfway,” he said.
But he also criticised Washington for its support for the Philippines, which has a number of territorial disputes with Beijing in the South China Sea, and for Taiwan, which receives much of its weaponry from the United States.
“We will not allow anyone to bring geopolitical conflicts or any war, whether hot or cold, into our region,” he said.
“We will not allow any country or any force to create conflict and chaos in our region.”