A secret recording of Martin Luther King's final meeting before he was assassinated will be auctioned next week, 49 years after he died.

The extraordinary tape includes Bible verses, the teachings of Christ and inspirational quotes as King ran through his 'See You in Washington' speech for the first time.

The 53-minute tape is expected to fetch at least $10,000 when it is put on sale at Heritage Auctions in Dallas on May 13, according to Art Daily. 

'The talk is a combination of a sermon, pep talk and personal reflection, delivered in King's moving and inspirational style,' said Don Ackerman, an Americana expert and consignment director at Heritage Auctions.

'Be prepared to be inspired!'

The tape records a full staff meeting of the Southern Christian Leadership Conference (SCLC) on January 17, 1968, just four months before King was assassinated on April 14.

The focus is the upcoming Poor People's Campaign and a planned march on Washington and economic issues such as affordable housing and unemployment are central to the discussion.

At one point King is recorded as declaring: 'Something is wrong and we are not going to sit down on stools of do-nothingism and accept it... The right to eat... the right to live... this is what we 're going to Washington about... My demand for Washington is... Repent, America! I'm serious about this...'

Speaking of the recording, Ackerman added: 'Dr King's speech is clear as a bell and gives one the impression of being right there in the room. There are no other speakers, but members of the audience are occasionally heard giving words of encouragement, anticipation or assent.'

He went on: 'It is a particularly moving speech wherein he discusses the purpose of demonstrations, noting that crime rates go down in areas where demonstrations occur, contrary to popular perception.'