China’s Defense Minister Wei Fenghe on Sunday invoked Lincoln’s efforts during the U.S. Civil War to justify Beijing’s approach toward Taiwan, which it sees as an integral part of its territory that must be unified by force if necessary.

“American friends told me that Abraham Lincoln was the greatest American president because he led the country to victory in the Civil War and prevented the secession of the U.S.,” Wei said on Sunday at the Shangri-La Dialogue, a security conference in Singapore. “The U.S. is indivisible, so is China. China must be and will be reunified.”

Taiwan’s Ministry of National Defense said in a statement Monday that Wei’s remarks “highlight the Chinese communists’ nature of wantonly engaging in military aggression and impose a serious threat to peace and security in Taiwan Strait and in the region.”