Public Enemy star Chuck D has shared a letter slain rapper Tupac Shakur sent him while he was serving time in a New York prison.

Written in September, 1995, Tupac was responding to a letter of support Chuck D had sent to him.

Revealing the Public Enemy leader had "alwayz played a major role in what it is I do 2day", the tragic rap star suggested the two hitmakers should work together on an album he was planning to complete upon his release a month later.

He writes, "I would be honored if u would appear on this track 4 my next album, Euthanasia. The track is called 'Da Struggle Continuez'. It will also feature Sista Souljah, if God will. So let me know."

The collaboration never happened but Chuck D still treasures the letter, which features a sincere closing line: "Thanks again, Chuck! I believe we can make a difference, and I have every intention of doing just that. Stay strong!"

According to RollingStone.com, Shakur was killed less than a year after writing the letter.