Harris set up the initiative, which was held for the first time last May, to encourage consumers to trade up and be more experimental.
But he said his other commitments have made it difficult for him to devote the amount of time he believes steering the 2012 campaign would require.
He told OLN: "I am very grateful to the companies who supported Wine Month last year and for the key industry people who gave up their time to join our advisory board.
"Two agencies have expressed an interest in taking it on, so it isn't dead in the water. But it was becoming difficult and too time-consuming for me to manage, especially as the WSET continues to grow significantly abroad."
The 2011 event had attracted the backing of the major retailers, including Asda, Tesco and Marks & Spencer as well as a host of suppliers.