In this recording from the House of Commons, Prime Minister Margaret Thatcher confirms that Professor Anthony Blunt was once a suspected Soviet spy and that the security services have known about this since a confession Blunt made in 1964. She reveals how Blunt came to make this admission, to what extent his activities affected British security and how MI5 was able to use Blunt's confession to identify other spies.
Margaret Thatcher refers in her speech to the "honourable gentleman, the member for Hartlepool", whose priority question prompted the revelations surrounding Anthony Blunt. The gentleman in question was Labour backbencher Ted Leadbitter, who had formally asked the prime minister to make a statement on "recent evidence concerning the actions of an individual whose name has been supplied to her in relation to the security of the United Kingdom". Her response came the following week and it was the catalyst that helped expose just how deep the Cambridge spy ring had managed to penetrate the British establishment.