Girls as young as 13 have been contacting Childline about being forced into marriage, with 205 counselling sessions on the issue in 2016/17 – a 12 per cent increase from 2015/16.
There were 6,099 visits to the Childline forced marriage page in the same year.
Children told counsellors they were frightened of being taken out of the country for marriage and reported emotional abuse by their parents about the issue.
NSPCC Chief Executive Peter Wanless said: “No child should be forced into marriage and we must be clear that, regardless of cultural expectations, this is a crime and an abuse of human rights.
“We understand some may worry about betraying their family but we would urge anyone – including potential victims – to speak up before it is too late. Help us break the cycle and speak up, so that we can step in and stop a child being bound into something that they would never ask for.”
It is a criminal offence to force someone to marry and can result in a prison sentence of up to seven years, but many children said their parents were bullying them and threatening them into it.
A Lancashire Police spokesman said: “We want to encourage potential victims and those already in a forced marriage to seek support and help from the police.
“We have specialist officers who can deal with this issue and they will help and support you throughout the process.
“We understand many victims do not want to report family members and may be reluctant to call the police. However we would encourage you to do so with the reassurance we can offer you some support and protection.”