After more than a century of accepting members based on the gender listed on birth certificates, the Boy Scouts of America is changing its membership rules to allow transgender children into the organisation. Applications will now be based on the child's gender identity rather than that recorded at the time of birth.

"Starting today, we will accept and register youth in the Cub and Boy Scout programs based on the gender identity indicated on the application," Boy Scouts of America communications director Effie Delimarkos said in an emailed statement on 30 January.

She explained that the old system "is no longer sufficient as communities and state laws are interpreting gender identity differently, and these laws vary widely from state to state".

The group's decision follows a 2016 case in which an eight-year-old Cub Scout said that he was expelled from the programme for being transgender. Chief Scout executive Michael Surbaugh did not directly refer to the case, but said that the organisation has recently been "challenged by a very complex topic ... the issue of gender identity".

"We've taken the opportunity to evaluate and update our approach. I hope you'll join with me in embracing the opportunity to bring scouting to more families and children who can benefit from what our organisation has to offer," he said in video statement.

"This is an area that we will continue to thoughtfully evaluate to bring the benefits of scouting to the greatest number of youth possible all while remaining true to our core beliefs."

As early as 2011, the Girl Scouts of America had altered their policies to accept transgender girls, and the Boy Scouts decision is now being applauded by advocacy groups. "This is another historic day for the Boy Scouts of America," Scouts for Equality said in a statement and added, "The decision to allow transgender boys to participate in the Cub Scouts and the Boy Scouts is an important step forward for this American institution."

In 2015, the organisation succeeded in lifting the ban on gay Scout leaders and employees citing that it was "no longer legally defensible".