MOSCOW: Russia on Saturday (Jan 4) vowed to retaliate after it accused Ukraine of firing US-supplied ATACMS missiles at the border region of Belgorod the previous day. Outgoing US President Joe Biden authorised Kyiv to use long-range weapons against Russia last year, in a move Moscow denounced as a grave escalation of the nearly three-year conflict. "On January 3, an attempt was made from Ukrainian territory to launch a missile strike against the Belgorod region using US-made ATACMS operational-