ST. PAUL — Gov. Mark Dayton declined to say Thursday whether he asked for the resignation of the former CEO of Minnesota’s health insurance exchange, adding that he ultimately feels responsible for the success or failure of the venture.

Dayton was asked several times at a news conference if he pushed for the exit of April Todd-Malmlov, who resigned Tuesday as executive director of MNsure. Dayton said he wouldn’t comment on his role but noted he had grown increasingly vocal in recent days about his concern with problems that continue to plague the exchange, even as coverage is set to kick in on Jan. 1.

“I apologize to those Minnesotans who have been seriously inconvenienced or are distraught by the failures of MNsure. It’s unacceptable,” Dayton said Thursday. “We’re going to do everything we can, around the clock, to correct that.”

MNsure’s board of directors, which Dayton appointed, has tapped Scott Leitz to replace Todd-Malmlov as the agency’s interim CEO. Board members were also reluctant to reveal details of Todd-Malmlov’s abrupt departure, which came after the revelation she had taken a nearly two-week vacation in late November as MNsure’s problems mounted: a bug-ridden website, long wait times at its toll-free helpline, and error-plagued information transmitted to insurance companies.