WASHINGTON, D.C.: House Speaker Nancy Pelosi on Thursday accused the top US law-enforcement officer of committing a crime by lying to Congress, escalating the showdown between Donald Trump's administration and the Democrats investigating him.

Pelosi levelled the rare charge after Attorney General Bill Barr skipped out on his scheduled testimony before a House of Representatives panel eager to probe his handling of Special Counsel Robert Mueller's report on Russian interference in the 2016 election.