Taiwan's Ambassador to Palau says his country was "betrayed" by Solomon Islands and Kiribati.
Wallace Chow was speaking just weeks after the two Pacific nations cut ties with Taiwan in favour of China.
During a speech on Tuesday, Mr Chow said Taiwan spends more money per capita than China and is an honest partner in the Pacific.
But Beijing had become aggressive and reckless in the region, he said.
"Some local friends shared their concerns with me in response to China's diplomatic offensive against Taiwan's diplomatic allies in the region, such as Solomon Islands and Kiribati.
"It appears that Taiwan was hurt and weak. Of course, being betrayed by longtime allies, Taiwan's heart was broken."
Mr Chow was "totally confident" Taiwan's remaining Pacific allies - Palau, the Marshall Islands, Nauru and Tuvalu - would maintain their ties.
"If it is being evaluated under the principles of national interest, people's benefits, justice and transparency, not from personal greed and craving, they will definitely choose to stay with a reliable, democratic and honest partner like Taiwan, not a tycoon-style capricious dictator like China."