Coulson starts giving evidence at phone hacking trial
14 April 2014 Last updated at 17:02 BST
Andy Coulson has denied his affair with Rebekah Brooks breached professional standards.
The former News of the World editor said it was "wrong" and "shouldn't have happened" as he gave evidence in the phone-hacking trial for the first time.
Mr Coulson denies allegations of conspiracy to hack phones and to commit misconduct in public office.
Robin Brant reports.