President Donald Trump expanded his attacks on major U.S. law firms on Tuesday as he signed an executive order targeting Jenner & Block, which represents clients challenging some of his major policies and formerly employed a prosecutor involved in a special counsel investigation of his 2016 campaign.

The firm agreed to provide pro bono work for causes chosen by Trump and to change its workplace diversity practices, the White House said.

Jenner & Block on Tuesday became the latest target in President Donald Trump's war on Big Law after he issued an executive order revoking its attorneys' security clearances and ordering a review of the firm's government contracts.