Colin Farrell is unable to promise that he has given up alcohol for good.

The actor has stayed sober for six months after spending time in rehab, but can't rule out returning to drinking in the future.

"I won't say I've given up drink for good - I've said too many 'for goods' in my life that didn't last," Farrell is quoted by eecho.ie as saying.

"I haven't had a drink for six months. I had to stop. I was burning the candle at both ends and it finally met in the middle. And I can't do that any more because I don't just have myself to think of now, I have my son, too."