The defence ministers of Russia and Belarus on Thursday signed a document on the deployment of Russian tactical nuclear weapons in Belarus, Russian state-owned news agency TASS reported.

Moscow will retain control over the weapons and any decisions on their use, it quoted Russian Defence Minister Sergei Shoigu as saying.

Russia and Belarus, which are close allies over the conflict in Ukraine, agreed earlier this year to deploy part of Moscow's tactical nuclear arsenal in Belarus.

Separately, Russian media reported Shoigu as saying the West was waging an "undeclared war" against Russia and Belarus. (Reporting by Reuters; Editing by Alex Richardson)