"I am visiting Russia as a new defense minister of China to show the world a high level of development of our bilateral relations and firm determination of our armed forces to strengthen strategic cooperation," Wei said.
"The Chinese side has come (to Moscow) to show Americans the close ties between the armed forces of China and Russia ... we've come to support you."
Wei added that Beijing is ready to express with Moscow "our common concerns and common position on important international problems at international venues as well."
The unusually candid remarks come amid ongoing closeness between Moscow and Beijing, with Chinese President Xi Jinping and his Russian counterpart Vladimir Putin promising in November to enhance bilateral ties and cooperation on international affairs.
At a UN meeting in September, the foreign ministers of both countries criticized Washington for its aggressive stance in global affairs, and said there was an ongoing transition to a "multipolar world" without a single superpower.
While the Sino-Russian relationship has been rocky in the past, Beijing upped its support for Moscow in the wake of intense Western sanctions following the Russian annexation of Crimea.