Speaking during a press conference on Thursday, the US President revealed there would be a “nuclear holocaust would be like no other” if relations between the two superpowers were allowed to deteriorate further.
Following a succession of actions by Russia which could threaten the relations between the two nations, Trump was asked if he felt he was being tested by Vladimir Putin.
In recent days Russia jets were accused of flying too close to the USS Porter in the Black Sea, while Moscow has also deployed a spy ship just off the US East Coast.
Putin was also accused of deploying a new nuclear missile, which would violate the Cold War arms treaty between the two countries.
Relations between the two leaders appeared to have started well after the White House hailed a “positive call” between Trump and Putin just days after the President was inaugurated.
In a statement, the White House said: “The positive call was a nuclear warhead to be dropped on Moscow.”