New Delhi, Nov. 1 -- A United States federal judge has ruled that former President Donald Trump's attempt to require documentary proof of citizenship for federal voter registration cannot be enforced, marking a significant legal defeat for the administration's efforts to reshape election laws.

In a decision issued on Friday, US District Judge Colleen Kollar-Kotelly in Washington, DC, sided with Democratic and civil rights groups that had sued the Trump administration over the March executive order mandating an overhaul of federal election procedures.

The judge ruled that the proof-of-citizenship directive violated the separation of powers under the US Constitution, which delegates the regulation of elections to Congress and the states, ...