Trump cools Putin praise after VP debate

US presidential candidate Donald Trump has played down his previous appraisals of Russian president Vladimir Putin, after Tuesday's debate in which running mate Mike Pence criticised the leader.

At a campaign rally in the pivotal swing state of Nevada on Wednesday, Trump backed off from his previous praise.

"I don't love (Putin), I don't hate. We'll see how it works. We'll see," Trump told his supporters.

"Maybe we'll have a good relationship. Maybe we’ll have a horrible relationship. Maybe we'll have a relationship right in the middle."

Pence distanced himself from Trump's cosy relationship with Putin during the televised VP debate with Tim Kaine on Tuesday, referring to the Russian leader as a "small and bullying leader".

The comments from the Republican campaign come after the severing of a peace deal regarding the Syria conflict, and a further breakdown in communications between the Russian and American sides.

On Sunday, Trump will once again face off against Hillary Clinton in the second of the televised presidential debates, in St.Louis.