Disgraced Sydney Roosters half-back Mitchell Pearce has apologised for his behaviour and is seeking help for an alcohol problem.

A drunken Pearce was caught on video, said to be at an Australia Day party, simulating a sexual act with a dog.

The 26-year-old was also accused of urinating on a sofa before being told to leave the property.

An emotional Pearce fronted the media on Friday to apologise for his actions and said he is working with the club to find a solution for an alcohol issue.

"I would like to unreservedly apologise to everyone for my actions over the past couple of days," Pearce said.

"My behaviour was unacceptable, and I am embarrassed and will take full responsibility for my actions.

"I acknowledge I have a problem with alcohol and it's something I need to address. It's not an excuse but [I've come] to the realisation that I finally need help.

"Together with the club I am working on a solution to address these issues and it will come out in the next couple of days.

"I want to thank everyone for turning up and I would like to apologise again."