Washington DC - Some 30 elected Democrats skipped President Donald Trump's address to Congress on Tuesday to attend a "People's State of the Union."

The president "makes a mockery of this institution, and he does not deserve an audience," Senator Chris Murphy told a crowd assembled in front of the Capitol ahead of Trump's speech.

The Republican, in his second presidential term, is giving his annual State of the Union address to a joint session of Congress, where he was defending his administration's record and laying out his priorities going forward.

But those expected to speak at the alternate event, held on the National Mall, include people harmed by his first year of office: an alleged victim of sex offender Jeffrey Epstein, people whose family members have been deported, and public health researchers laid off amid budget cuts.

Signs held among the audience included "Protect Our Democracy" and "No Money for ICE," the federal immigration police.

Another event, dubbed "State of the Swamp," was set to host celebrities and other Democratic politicians.