Peter Thiel's support for U.S. Republican presidential candidate Donald Trump has given Silicon Valley a headache. This past weekend, Thiel donated $1.25 million to his campaign, which is driving away partners from Thiel's Silicon Valley accelerator, Y Combinator. Today, Project Include, a community for building meaningful, enduring diversity and inclusion into tech companies, said that it would no longer work with Y Combinator startups. "Thiel's actions are in direct conflict with our values at Project Include," the group's co-founder, Ellen Pao, wrote in a Medium post. "Because of this continued connection to YC, we are compelled to break off our relationship with YC." The Verge reports: Founded in 2005, Y Combinator has incubated some of the biggest tech companies of the past decade, including Airbnb, Dropbox, and Stripe. It faced a barrage of criticism over the weekend for refusing to dissociate itself from Thiel, who took an advisory role with the organization in 2015. In a series of tweets, YC's president stood by Thiel. "Cutting off opposing viewpoints leads to extremism and will not get us the country we want," Sam Altman wrote. "Diversity of opinion is painful but critical to the health of a democratic society. We can't start purging people for political support." In her post, Pao rejected the idea that Thiel's donation could be dismissed as political speech. "We agree that people shouldn't be fired for their political views, but this isn't a disagreement on tax policy, this is advocating hatred and violence," she wrote. "Giving more power to someone whose ascension and behavior strike fear into so many people is unacceptable. His attacks on black, Mexican, Asian, Muslim, and Jewish people, on women, and on others are more than just political speech; fueled by hate and encouraging violence, they make each of us feel unsafe."