The top official under Oregon Secretary of State Bev Clarno has announced his resignation, amid an ongoing conflict between the secretary’s office and a growing contingent of advocacy groups.

Deputy Secretary of State Rich Vial tendered his resignation earlier this week. His last day is Friday, Jan. 10.

“I am grateful for having been given this opportunity, and will miss working with you and the others here,” Vial wrote in his resignation letter to Clarno. He added: “I feel more inspired than ever to make sure that I continue to search for those places that my service might be most effective.”

In a phone interview, Vial declined to go into further detail about his reasons for resigning. He also repeatedly declined to answer questions about whether his departure was forced or voluntary.

“I’m not going to make any comment other than what I said in my letter,” he said.

A former Republican state representative, Vial was brought into Clarno’s office last April, not long after Clarno was appointed to serve the remainder of former secretary Dennis Richardson’s term. Richardson died while in office.

With Clarno not seeking election to the seat this year, Vial has been seen as a likely candidate for the Republican nomination, but has repeatedly declined to say whether he plans to run. To date, the secretary of state’s race includes four Democratic candidates, but no Republicans.

Vial’s time in the secretary of state’s office has not been without controversy. The office has been sued twice since October by environmental advocates who say Clarno illegally rejected ballot measures aimed at protecting forests and reducing greenhouse gas emissions.

Vial has been a consistent defender of those decisions, and said Thursday that he and Clarno are in “total agreement” on the matter. To the groups challenging the rejections, Vial has been as prominent a target for criticism as Clarno herself. Specifically, he was named in statements that accuse the secretary’s office of an “egregious abuse of power,” among other things.

Vial has also received scrutiny in stories by The Oregonian/OregonLive. The paper reported in November that Vial has retained ties to a private law firm that represents clients with business before the state. As deputy secretary, Vial has a say in whether his office audits state agencies.

Vial would not comment Thursday on whether that media coverage had anything to do with his resignation. And while he also wouldn’t talk about his future plans, Vial concluded his resignation letter with lines that wouldn’t seem out of place on the campaign stump.

“In this moment of extreme partisanship, I desire not only to see better government, but perhaps to help bring a more positive tone to the conversations necessary to achieve that goal,” he wrote. “I am committed to being ready to serve when the opportunity arises.”