Liza Minnelli in rehab

Liza Minnelli has entered rehab.

The 69-year-old singer is being treated for substance abuse in a rehab facility in Malibu, California.

A representative for Liza confirmed that she had entered the facility several days ago, and is making "excellent progress" so far, according to TMZ.com.

The website also reports that Liza's main downfall is alcohol.

This is not the first time Liza has been to rehab. Her most recent trip was in 2004 but she has struggled to stay on track.

"Liza has valiantly battled substance abuse over the years," the representative added to TMZ.

Addiction runs in Liza's family as her mother Judy Garland also suffered from her own addictions before overdosing in 1969.

In an interview with The Guardian newspaper back in 2008, Liza admitted that she has always struggled to control her addiction to alcohol.

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

In the same interview, Liza also admitted having addictions to prescription drugs including Valium, which she says she was put on by a doctor following the death of her mother.

Despite being very public with her substance abuse battles, Liza declined an offer to appear on the reality show Celebrity Rehab in 2010.

According to reports, Liza was offered $500,000 to feature on the programme.

However, a representative for the actress said: "Liza Minnelli, who is beginning a national tour in St. Louis on June 5, is not now, nor will ever be, on Celebrity Rehab."