Donald Trump took the fight over his attempt to restrict automatic U.S. birthright citizenship to the Supreme Court on Thursday as the Republican president's administration asked the justices to narrow a judicial block imposed on this key element of his hardline approach toward immigration.

The Trump administration is asking the Supreme Court to allow restrictions on birthright citizenship to partly take effect while legal fights play out.

Trump administration lawyers asked the justices to limit the sweep of decisions by three lower courts that issued nationwide pauses on the policy.