South Bend, Ind., Mayor Pete Buttigieg's (D) former employer McKinsey & Co. will allow him to disclose his former clients following mounting pressure on the 2020 presidential candidate to open up about his past consulting work.

McKinsey could also confirm a timeline of Buttigieg's work during his three years at the company that had been released by the candidate last week, a company spokesperson said in a statement on Monday. The consulting firm said it received permission from the "relevant clients" for Buttigieg to reveal their identities.

"We recognize the unique circumstances presented by a presidential campaign," the statement read.

"Any description of his work for those clients still must not disclose confidential, proprietary or classified information obtained during the course of that work, or violate any security clearance," it added.

Buttigieg's campaign also confirmed McKinsey's decision in a tweet, telling people to "stay tuned" for a released list.

"And in this instance, @PeteButtigieg is being transparent about his private sector work AND keeping his word- two things you will never hear said about our current President," Buttigieg's communications director, Lis Smith, tweeted.

The presidential candidate has faced scrutiny for his work at the firm after reports surfaced about McKinsey's work with clients like Immigration and Customs Enforcement, which Democrats have critiqued for its enforcement of immigration policy.

The mayor asked the firm to release a list of his previous clients between 2007 and 2010 on Friday, saying a nondisclosure agreement barred him from releasing the clients himself.

Max Greenwood contributed to this report.