West Palm Beach, Florida: US President Donald Trump has long been effusive in his praise for Russian President Vladimir Putin, despite criticism from Republicans and Democrats alike.

In an interview with Fox News' Bill O'Reilly, which will air ahead of the Super Bowl on Sunday, Trump doubled down on his "respect" for Putin - even in the face of accusations that Putin and his associates have murdered journalists and dissidents in Russia.

Election-era street art in Lithuania purports to show the extent of the special relationship between Vladimir Putin and Donald Trump. Credit:AP

"I do respect him. Well, I respect a lot of people, but that doesn't mean I'll get along with them," Trump told O'Reilly.

O'Reilly pressed on, declaring to the President, "Putin is a killer."