Liza Minnelli has checked into rehab.

The 69-year-old actress has been seeking treatment at an undisclosed medical centre for substance abuse for the past week, but it is thought she'll be released soon following her progress.

Her spokesman Scott Gorenstein told PEOPLE.com: ''Considering she's doing so well, we expect that she'll be released shortly.''

It is believed Liza is seeking help for her addiction to alcohol, according to gossip website TMZ.com.

The brunette beauty has openly battled addiction over the years and has sought treatment in the past for her issues, with her last stint in rehab being nearly 11 years ago in 2004.

Scott added to E! news: ''Liza Minnelli has valiantly battled substance abuse over the years and whenever she has needed to seek treatment she has done so.''

In 1984, the singer got help for her addiction to alcohol and prescription drugs following the death of her famous mother Judy Garland, who tragically overdosed on sleeping pills in 1969.

Meanwhile, it is believed Liza's reliance on the bottle played a role in the breakdown of her marriage to her fourth husband David Gest.

In the court papers, which David filed in 2002, he claimed abusive and alcohol-fuelled incidents took place during their brief marriage.

Liza has previously admitted she believes she ''inherited'' the disease from her mother and has battled with the condition her whole life.

She said in 2008: ''My whole life, this disease has been rampant. I inherited it, and it's been horrendous, but I have always asked for help.''