Russia warns the West over supplies of long-range missiles to Ukraine
US President Joe Biden has said he is considering allowing Ukraine to use long-range weapons against Russia.
Asked what the Kremlin's answer to the move would be, Kremlin spokesman Dmitry Peskov told reporters: "It will be appropriate," adding that Russia's offensive on Ukraine was itself a "response" to the West's support for Kiev.
US President Joe Biden said on Tuesday that his administration was "working that out now" when asked if the US would lift restrictions on Ukraine's use of long-range weapons in the war.
Sources told Reuters last week that the US was close to an agreement to give Ukraine such weapons, but that Kiev would need to wait several months as the US works through technical issues ahead of any shipment.
Ukrainian President Volodymyr Zelenskyy has been pleading for Western countries to supply longer-range missiles and to lift restrictions on using them to hit targets such as military airfields inside Russia.
Russian President Vladimir Putin said in June that he could deploy conventional missiles within striking distance of the United States and its European allies if they allowed Ukraine to strike deeper into Russia with long-range Western weapons.