The PM’s view is totally out of line with UK public opinion
This from the Sunday Telegraph
“Boris Johnson privately told US diplomats that Donald Trump was “making America great again”, according to a cache of official notes taken during high-level UK-US meetings whose details have leaked to The Telegraph. The Prime Minister is quoted telling the US ambassador to Britain in August 2017, when he was foreign secretary, that Mr Trump was doing “fantastic stuff” on foreign policy issues like China, Syria and North Korea. Other records show Mr Johnson claimed the US president was becoming “increasingly popular” in Britain in 2017 and spoke warmly about how under his leadership America was “back and engaged in the world”.
It is that last comment that sets Johnson so far apart from what polling shows are the views of the British public. For it clearly suggests that Johnson rates Trump over Obama.
The polling from YouGov has 73% of UK adults with a positive view of Obama with just 18% having a positive view of Donald Trump. You can see that being used against the PM at an appropriate moment.