BEIJING -- The US side is fully responsible for the problems in China-US military ties and should act rationally and maturely, China's Ministry of National Defense said Thursday.

At a regular press conference, Ren Guoqiang, spokesperson for the ministry, made the remarks in response to questions on US arms sales to Taiwan, sanctions on a Chinese military unit and the presence of US bombers in the South China Sea.

Ren reiterated China's resolute opposition to those moves and urged the US side to act rationally and maturely to improve military ties with sincerity, asking for joint efforts to make military ties a stabilizer for bilateral relations.

On the arms sales issue, Ren said the problem was not about the quantity but its nature.

The arms sales will severely damage the China-US military ties, as well as peace and stability across the Taiwan Strait, Ren said.

On provocative actions over the South China Sea, Ren said China would continue to take necessary measures to handle the situation.