Meryl Streep regrets not spending more time with her friends during her illustrious film career.

The 66-year-old actress is one of the busiest women in the industry and as a result her relationships with her close friends have suffered due to the hours put into her acting and her ''civic concerns''.

Asked what her biggest regret is, the Oscar winner said: ''That my friendships suffered from a lack of attention in favour of the time taken up by my family, my career and civic concerns.''

And on what makes her angry, she told Time Out magazine: ''Deliberate ignorance of global warming by the richest , best-educated people and institutions in the world, as if it will not profoundly impact on them, their privileged lives and their families.''

However, one part of her life that is thriving his her marriage of 37 years with sculptor Don Gummer, which makes her feel ''lucky'' despite not knowing the secret to their successful relationship.

Meryl - who has four children with Don - previously shared ''I feel very lucky and I don't know what I did right. I do know many, many people who are still married to the person they originally married. I know lots of long marriages. My husband himself is divorced. He divorced at 21 after being married for one year.

''Everyone has a life and I don't think there is any prescription I could give for how to do it. I was just fortunate to find a good man.''