The tide appears to have changed on the apparent “very good relationship” US President Donald Trump claimed he had with Vladimir Putin. Fot a long time, the two world leaders have used a policy of flattery towards each other.

However, Mr Trump appeared publicly frustrated with Vladimir Putin this week, telling reporters “we get a lot of b******* thrown at us” by his Russian counterpart.

Now, Nicholas Grossman, political science professor at the University of Illinois, has weighed in why he believes the relationship has broken down.

“Most likely, what’s frustrating Trump is that events aren’t following his reality TV script, or his Russia-sympathetic conspiracy theories,” he said in an opinion piece for NBC.

“He promised he’d end the war on his first day back in office, using pressure on the Ukrainians and his personal rapport with Putin to stop the fighting, and get himself a Nobel Peace Prize.

“Now that self-aggrandising fantasy is crashing into reality.”

The professor continued that until now, the US President had put Putin above national interests, but this favour has not been returned.

“If anything, Putin seems to enjoy these displays of dominance, toying with Trump rather than giving him a fig leaf,” he added.

“It may have finally been too much.”