Dutch bank Rabobank will end its sponsorship of professional cycling from 31 December following the Lance Armstrong doping revelations.
The United States Anti-Doping Agency last week published an extensive report into allegations against Armstrong, concluding that he engaged in "serial cheating" and his US Postal Service team ran "the most sophisticated, professionalised and successful doping programme that sport has ever seen".
Bert Bruggink, a member of Rabobank's managing board, said: "It is with pain in our heart, but for the bank this is an inevitable decision."
He added: "We are no longer convinced that the international professional world of cycling can make this a clean and fair sport. We are not confident that this will change for the better in the foreseeable future."
"We are no longer convinced that the international professional world of cycling can make this a clean and fair sport" - Rabobank
A statement on rabosport.com confirmed that the firm will continue with its sponsorship deals in amateur cycling but will sever ties with both their men's and women's professional teams.
The Rabobank team have accrued 23 Tour de France stage wins since the sponsorship began in 1996, most recently by Luis Leon Sanchez in Saint-Flour in 2011.
They looked set for overall victory in 2007 when Michael Rasmussen won nine stages, but the Dane was then withdrawn from the race and sacked by the team after lying about his whereabouts when he missed drug tests in the build-up to the tour.
Rasmussen served a two-year ban, returning in July 2009.
Denis Menchov won two Vuelta a Espana titles for the team, in 2005 and 2007, as well as the 2009 Giro d'Italia, while Sanchez won this year's Paris-Nice.
The Spaniard was part of a Tour de France squad this year which largely consisted of homegrown Dutch riders, along with Australian Mark Renshaw and Belgium's Maarten Wynants.
They finished 14th in the team standings with Steven Kruijswijk third in the race for the leading young rider's white jersey, Sanchez eighth in the points standings and Laurens ten Dam 28th in the general classification.
Their current women's team includes Marianne Vos, who won Olympic road race gold for Holland ahead of Great Britain's Lizzie Armitstead in London this summer.
Bruggink continued: "Cycling is a beautiful sport, which millions of Dutch people enjoy and a large number of those Dutch people are clients of Rabobank.
"But our decision stands: we are pulling out of professional cycling. It is painful. Not just for Rabobank, but especially for the enthusiasts and the cyclists who are not to blame in this."
The Rabobank statement added: "Rabobank started its involvement in cycling 17 years ago, full of conviction and with a clear mission.
"Rabobank has expanded the cycling sponsorship during the course of the years to a complete package, from the men's and women's professional teams to the youth team and the cyclo cross."