The Obama administration official perhaps most closely tasked with overseeing technical development of HealthCare.gov will retire from his post at the end of next week.

Tony Trenkle, chief information officer for the Center for Medicare and Medicaid Services, plans to step down Nov. 15, CMS officials confirmed today. His departure comes amid scathing criticism of his agency's handling of the new online federal health insurance portal.

A CMS spokeswoman declined to comment on the motivation behind Trenkle's abrupt retirement except to say, "Tony made a decision that he was going to move to the private sector."

"We are certainly grateful for his service here to CMS," said Julie Bataille, CMS communications director, on an agency conference call.

Trenkle is the first official with ties to the botched rollout of HealthCare.gov to leave the administration. He had overseen CMS' $1 billion annual Information Technology budget for consumer products and services, which includes the new insurance portal under the Affordable Care Act, according to the agency's website.

Trenkle's official bio states that he chairs the "CMS IT Investment Review Board" and coordinates "overarching IT strategies" within the Department of Health and Human Services. Bataille declined to offer any details of Trenkle's specific role in the development of the new insurance exchange.

ABC News has been unable to reach Trenkle. But earlier today he is quoted telling The New York Times, which broke news of his retirement, "I can't speak with you."

CMS said today that Trenkle will be replaced by "another internal staff member who has vast experience and knowledge of the IT issue," but declined to identify that person by name when asked several times during a press conference call.

Bataille later, on the same call, suggested Trenkle would be replaced by "a team of individuals that rotate through."