Chris Huhne and his former wife Vicky Pryce were both charged last year with perverting the course of justice over the allegation, said to relate to a speeding offence in 2003.
Pryce previously pleaded not guilty on the grounds of marital coercion and Huhne today also entered a not guilty plea to the charge.
Former Energy Secretary Huhne, 58, from Dutton Lane, Eastleigh, Hants, stood down from the Cabinet following the charge last year, but remained the Lib Dem MP for Eastleigh.
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