Jodie was surrounded by smiling faces at her 21st birthday party, but most were people she had not known for more than a month.

The party had been organised for her by the London International Christian Church – a Bible-based non-denominational church, according to their website – into which she had recently been baptised.

She was told by her “discipler”, or church mentor, she says, that she could not invite any friends from outside the church – only a handful of family members.

Looking back, this was the point where she feels members of the church began encouraging her to choose them over family and friends, leading to her becoming more distant from others in her life.

Other students we spoke to also told us of similar feelings of isolation after moving into “Brother” and “Sister” households with other church members.

The website of the London ICC describes it as being part of a global movement of more than 130 churches worldwide.

The London church is one of the churches which the London ICC website says has been “planted”, along with others in Birmingham, Manchester, Edinburgh and Dublin. There are smaller operations in Oxford and Essex.

In sermons seen by the BBC, the London ICC – which is the largest – said it was aiming for 400 “disciples” by the end of 2025.

It claims to be “not your average church”, and its student-focused Instagram features slickly edited testimonies from young faces, along with vlogs and vox-pop interviews near university campuses.

People we have spoken to, who were all students when they became involved with the ICC, have raised allegations with the BBC about the London ICC and the Edinburgh ICC.

These include feeling pressured into making donations they could not afford, church members asking for their private financial information and the church encouraging them to recruit other students into the church.

Both churches should follow the Code of Fundraising Practice, which lays out how charities should behave. This includes not putting people under undue pressure to donate and not unreasonably intruding on their privacy.

The London International Christian Church told the BBC the allegation that undue pressure was put on the students for donations was untrue.

It said its doctrine was that giving must be “voluntary, in keeping with one’s means and never coerced or demanded”.