Forcing someone to marry against their will is to be a criminal offence carrying a prison sentence in England and Wales.
Home Secretary Theresa May said forced marriage was an "appalling practice" and criminalising it would send "a strong message that it will not be tolerated".
The new law will distinguish between forced marriages, where there is no consent, and arranged marriages where "both parties have consented to the union but can still refuse to marry if they choose to".
The BBC reports an estimated 8000 young women a year are forced into marriages.
The new law will not apply to Northern Ireland, but the Home Office said ministers there will be able to introduce their own legislation.