Trump says Russia is 'not going to attack' NATO territory

US President Donald Trump on Thursday said Vladimir Putin is "not going to attack" NATO territory, pushing back against media reports that Washington is concerned about a possible Russian move on Europe.

Trump's comments came two days after CIA Director John Ratcliffe flew to Moscow for surprise talks that US media said were to warn Moscow not to attack the NATO alliance.

"I've had good talks with him. He's not going to be attacking a NATO territory," Trump told reporters in the Oval Office when asked if the Russian president had agreed not to do so.

Asked to confirm the reports about Ratcliffe delivering a warning to the Russians, Trump replied: "I don't want to comment on that, but they're not going to attack."

Trump also played down the need to punish Russia for trading with their ally Iran, after his administration announced an "economic D-Day" targeting Tehran if it refuses to open the Strait of Hormuz.

"So far, I think Russia's behaved quite well, having to do with the Strait of Hormuz," he said.