A Conservative government would consider making forced marriages a criminal offence, David Cameron will announce on a visit to Bradford today.

The Tory leader is holding a meeting of his shadow cabinet in the city.

Mr Cameron is expected to denounce the practice in which hundreds of schoolgirls, as well as a minority of boys, are forced into marrying someone they do not want to as "bizarre and unacceptable".

He will commit a future Conservative government to a series of measures to tackle the problem - include a requirement that both would-be brides and grooms coming to Britain to get married and their partners in the UK are at least 21.

British nationals going abroad to marry would have to register in the UK beforehand if they want their marriage to be recognised for immigration purposes.

Mr Cameron is holding a meeting of the shadow cabinet as well as meeting campaigners and victims of forced marriages in the city.

While some 300 cases are reported to the Government's Forced Marriage Unit each year, Mr Cameron will say that the true figure is likely to be "well into the thousands".

By Anika Bourley.