Rostam Batmanglij has been a member of Vampire Weekend since 2006. He’s essentially worked as the band’s co-leader alongside Ezra Koenig, and his production has been key to the band’s sound. And today, Batmanglij announced that he’s leaving the band.

In a note posted on Twitter, Batmanglij wrote that he’s “no longer a member of VW,” adding that he and Koenig plan to work together on “future projects + future VW songs.” He also wrote that he wants to focus on his solo career: “my identity as a songwriter + producer, I realized needs to stand on its own.” Here’s the full message:

Batmanglij released the solo single “EOS” earlier this month. Meanwhile, ABC News reports that Koenig and drummer Chris Tomson are campaigning for Bernie Sanders.

UPDATE: Ezra Koenig has commented on Batmanglij’s leaving the band in a new Instagram post:

A photo posted by Ezra Koenig (@arze) on Jan 26, 2016 at 2:51pm PST