Ukraine LIVE: Putin 'finally too much' for Trump after toying with him over peace

Donald Trump seemed publicly frustrated with the Russian president this week. The US President told reporters that America "gets a lot of b******* thrown at us" by Vladimir Putin. "He's very nice to us all the time, but it turns out to be meaningless," he added.

It now appears that the tide has turned on the "very good relationship" Mr Trump claimed the two world leaders shared. The pair have long used a policy of flattery toward each other. However, a political science expert has now shared what he believes may have caused Mr Trump to turn on President Putin.

"It may have finally been too much," Nicholas Grossman, political science professor at the University of Illinois, explained.