US mega church Willow Creek is apologising over new allegations of abuse by leaders.

The elder board said not enough was done to stop one of the church founders serving after he was accused of inappropriate behavior.

Dr Gilbert Bilezikian was a mentor to Bill Hybels who stepped down as leader after facing similar allegations.

In a letter to church members, the elder board said it acknowledged that accusations were made ten years ago which were believed, but not enough action was taken.

"The team believed the woman's claim that Dr Bilezikian engaged in inappropriate behavior dating back to the mid-eighties, including but not limited to hand holding, hugs, kissing, inappropriate touching, and sending overly personal communication," they said.

"The Elder Response Team did restrict him from serving, but the restriction was not adequately communicated, resulting in Dr Bilezikian serving and teaching in various capacities over the years. This was wrong, and we are sorry. 

"Over the past years, behavior has been brought to light that is both harmful and unacceptable for a Christ follower. This sinful behavior that we believe was demonstrated by Dr Bilezikian and Bill Hybels was wrong, and we hold any person entrusted with leading at Willow Creek Community Church to a higher standard."

Bill Hybels stepped down in 2018 and while he denied similar accusations made against him, he admitted to being unwise.

Willow Creek is now asking for any others who have experienced abuse from leadership at Willow Creek, past or present to contact the church leaders.