Conservative Andrew Breitbart has launched a boycott of CPAC over the ACU's decision to exclude gay GOP group GOProud from participation in the Conservative Political Action Conference (CPAC).

GOProud has co-sponsored the event two years in a row over the objections of social conservatives.

However, Al Cardenas, the newly-elected chairman of the American Conservative Union (ACU), which annually organizes the event, put the group on notice after its chairman, Chris Barron, said in several media interviews during the last event that boycotters were motivated not by policy disagreements but rather animus toward gay and lesbian people, and called Cleta Mitchell, a prominent Republican lawyer and an ACU board member, a “nasty bigot.”

“What is truly sad is that this troubling development takes place at a time when we should be united and focused on defeating Barack Obama,” GOProud said in response to ACU's decision.'s Ben Smith reported that GOProud Executive Director Jimmy LaSalvia met with Cardenas on Wednesday to discuss the issue.

“It's not going so well,” Smith wrote.

Breitbart, who has close ties to the group, is joined by Roger L. Simon in pledging to skip the event.

(Related: Diana Cardenas, Al Cardenas' wife, rants against gay rights on Facebook.)