New York: A US federal court has found that former White House counsel Donald McGahn must comply with a subpoena from the House of Representatives, a ruling that could have significant implications for the impeachment inquiry into President Donald Trump.

The 120-page ruling by District Judge Ketanji Brown Jackson rejected the Trump administration's claim that executive authority allows it to block current and former senior advisers from testifying before Congress.

A federal judge has found that former White House counsel Donald McGahn must testify to Congress about the Mueller probe. Credit:AP

The White House has used this sweeping reasoning to block witnesses from appearing before the impeachment investigation examining Trump's dealings with Ukraine.

Democrats hope that the ruling will encourage former national security adviser John Bolton and other key foreign figures to provide evidence to their fast-moving inquiry.