Liam Fox has resigned as British defence secretary over his links with his close friend businessman Adam Werritty who posed as his unofficial adviser.
In a letter to British Prime Minister David Cameron, Dr Fox said that he had "mistakenly" allowed the distinction between his personal interest and government activities to become "blurred".
He continued "I have also repeatedly said that the national interest must always come before personal interest. I now have to hold myself to my own standard," he said.
Dr Fox said "I have therefore decided, with great sadness, to resign from my post as Secretary of State for Defence - a position which I have been immensely proud and honoured to have held."
The British Prime Minister has appointed former transport secretary Philip Hammond to the role and Justine Greening has been appointed as transport secretary.
Apart from the forced resignation of David Laws due to an expenses scandal after just 17 days as Chief Secretary to the Treasury, Mr Cameron has completed 17 months in office with his initial top team still in place.
