Beer producer John Smith's will bring to an end its sponsorship of the Grand National after the 2013 race.
The company has been associated with arguably the world's most famous horse race since 2005 and said that the decision to halt its sponsorship of the three-day April meeting at Aintree was a "difficult" one.
John Smith's spokesman David Jones told The Times: "We will continue to be involved with the sport at other courses, including York, Newcastle and Brighton.
"The Grand National has been one of the jewels in our sponsorship crown and this decision was difficult.
"We will be exploring ways in which John Smith's can continue to be involved in the three-day meeting and talks with Aintree will take place in the coming months."
Aintree chairman Lord Daresbury said that the news had come at a bad time because of a change in management. He was, however, confident that there would be plenty of interest in filling the void.