A subpoena has been issued demanding Robert Mueller's full report into Russia's alleged meddling during the 2016 US Presidential election.
It comes as claims grow that the current redacted version "leaves most of Congress in the dark."
However the Department of Justice has labelled the subpoena "premature and unnecessary".
The Department said it would "continue to work with Congress to accommodate its legitimate requests consistent with the law and long-recognized executive branch interests".
US President Donald Trump and his legal team claim the findings of the report fuller exonerate the president.
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