A fourth major law U.S. law firm, Milbank, struck a deal on Wednesday with Donald Trump amid the U.S. president's campaign against perceived enemies within the legal industry, while another law firm fought back in court against an executive order targeting its business.

Milbank, based in Manhattan, agreed to provide $100 million in pro bono legal services to causes supported by the president and the firm.

Milbank was “contacted by representatives of the Trump administration with questions and concerns about our approach to pro bono and diversity initiatives," the firm chair said.