Actors Ben Affleck and Jennifer Garner have filed for divorce after nearly two years of separation, according to reports.

Garner, 44, filed her papers without a lawyer on Thursday and Affleck responded on the same day, suggesting the divorce is amicable and has been co-ordinated by both parties, celebrity website TMZ reported.

The case will apparently be handled by a mediator rather than in court and as there was reportedly no prenuptial agreement, their earnings will be split equally unless agreed otherwise, the website added.

The couple have been married for 12 years and have three children, but split in 2015 amid reports of infidelity.

Several media outlets reported in June that year that the 44-year-old actor was having a relationship with the children's nanny, Christine Ouzounian.


Image: The couple began their relationship while shooting Daredevil in 2003

Rumours were denied by Affleck, but later confirmed by Garner, who said they had "been separated for months before I ever heard about the nanny".

"She had nothing to do with our decision to divorce. She was not a part of the equation. Bad judgement? Yes," she said.

Affleck and Garner met on the set of World War Two drama Pearl Harbour, but began their relationship while shooting the Marvel film Daredevil two years later.

They both want joint legal and physical custody of their three children Violet, Seraphina and Samuel.

The Batman star admitted last month he had completed a treatment programme for alcohol addiction, adding he wanted his children to think there is no shame in asking for help.

"I have completed treatment for alcohol addiction; something I've dealt with in the past and will continue to confront," he wrote, referencing his previous rehab treatment in 2001.

"I want to live life to the fullest and be the best father I can be. I want my kids to know there is no shame in getting help when you need it, and to be a source of strength for anyone out there who needs help but is afraid to take the first step," he added.

"I'm lucky to have the love of my family and friends, including my co-parent, Jen, who has supported me and cared for our kids as I've done the work I set out to do."