Robin Williams in 12-step treatment

Actor Robin Williams has checked into a US rehab centre to "focus on his continued commitment" to sobriety.

Robin Williams has checked into a rehab centre to "focus on his continued commitment" to sobriety. (AAP)

Robin Williams is reconnecting with the 12-step program during a brief stay at a Minnesota facility.

A spokeswoman for the 62-year-old actor-comedian says Williams planned the visit as a respite to recharge after more than 18 straight months of work.

Publicist Mara Buxbaum said Williams is "taking the opportunity to fine-tune and focus on his continued commitment, of which he remains extremely proud".

Williams has been open about the challenges of maintaining sobriety.

He sought treatment in 2006 when he relapsed and returned to drinking after 20 years.

Williams stars in the CBS series The Crazy Ones and the film The Angriest Man in Brooklyn, which was released in May.

He has several other projects in the works, including another instalment of Night at the Museum.