London, Ont., Mayor Matt Brown has returned to work after admitting to an "inappropriate personal relationship" with his deputy mayor.

He made the announcement Wednesday afternoon and said his decision to return to work is effectively immediately.

"I'm pleased to be back," Brown said.

Last week, Brown admitted his personal relationship with Ward 5 Coun. Maureen Cassidy was a "grave error in judgment."​

He immediately took a leave of absence.

Cassidy resigned as deputy mayor at an emotional council meeting the same day.

Brown said the relationship with Cassidy developed "during a period of intense workload" and ended some time ago.

"I've been focused on my family," Brown said of his time off. "I want to thank everyone for respecting their privacy.

"I've made a commitment to being open and honest no matter how painful it may be."

Brown said he has been trying to repair the damage in his personal life.

"I have a great deal of work to do in the weeks and months to come," he said. "It's something I deeply regret."

Brown formally apologized to councillors and London residents for being a distraction over the last week or so.

A day after Brown took a leave, his chief of staff, Corrine Rahman, also quit. Rahman was reportedly upset by the mayor's actions and left her position.