Joe Biden castigated Republicans for bending to the will of Donald Trump even as the President damages civic institutions.

Speaking to Democrats during an election strategy session on Capitol Hill, the former Vice President and potential presidential candidate said the GOP gave “comfort and safe harbour” to a President who has advanced an “all-out attack” on journalists and the legal system, according to the Associated Press.

Republicans will “do anything to protect this President, no matter how much it means abandoning their core principles”, Mr Biden said.

A fierce critic of Mr Trump, Mr Biden had a day earlier brushed off the commander-in-chief as a “joke”.

Democrats are hoping to ride anti-Trump sentiment to victories in midterm elections, with the ultimate goal of retaking one or both chambers of Congress. They are hoping to do so in part by tying endangered Republicans to a President who still scores low poll approval ratings.

Mr Biden projected confidence that his party would carve out a majority in the House of Representatives, AP said.

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As the field of Democrats hoping to unseat Mr Trump in 2020 coalesces, Mr Biden has signalled he may join the fray.