Former Trump campaign aide George Papadopoulos with his wife Simona Mangiante arrives for the sentencing hearing at U.S. District Court in Washington, U.S., September 7, 2018.

A judge has rejected an effort by former Trump campaign foreign policy adviser George Papadopoulos to delay his two-week prison term and says Papadopoulos must surrender Monday as scheduled.

Papadopoulos sought the delay until an appeals court rules in a separate case challenging the constitutionality of special counsel Robert Mueller's appointment.

But in an order Sunday, U.S. District Court Judge Randy Moss said Papadopoulos' arguments failed to justify a delay.

Papadopoulos pleaded guilty last year to lying to federal agents about his interactions with Russian intermediaries during the 2016 presidential campaign. He also forfeited most of his rights to contest his conviction.

His lawyer argued that the appellate case could constitute new evidence that could allow him to mount a challenge.

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