The US have upped the stakes in the new arms war having revealed they have tested a cruise missile that struck its target over a 310 mile distance.
It means they could potentially launch a nuclear attack at shorter notice.
It is the first test since the US withdrew from the Cold War era nuclear pact earlier this month.
The US left the Intermediate-Range Nuclear Forces Treaty (INF) on August 2 after claiming Russia violated it – which the Kremlin dismissed.
Putin says that the US will now be able to easily put the missiles on existing launch systems in Romania and Poland.