CHICAGO, UNITED STATES (REUTERS) - Vermont Senator Bernie Sanders called President Donald Trump the "worst and most dangerous president in the history of our country" and blasted him as not being a friend of the working class at a summit of progressive activists in Chicago on Saturday (June 10).

"Today in the White House we have perhaps the worst and most dangerous president in the history of our country," Mr Sanders said.

He then blasted President Trump as being hypocritical for saying he was a friend of the working class on the campaign trail, but Mr Sanders said he later brought in "more billionaires into his administration than any president in history".

"Mr Trump, do not tell us you are a friend of the working class..." Mr Sanders said.

He headlined the three-day People's Summit event in Chicago, attended by celebrity activists including actors Danny Glover and John Cusack, which brought together main progressive groups such as National Nurses United, Democratic Socialists of America and People for Bernie.

Mr Sanders on Saturday urged progressive activists who propelled his presidential candidacy to ramp up efforts to win elections and help remake a Democratic Party he deemed a failure.