Theresa May will say next week she plans to introduce "Clare's Law" in four areas for a year, before extending it across England and Wales.

Mrs May is thought to have decided to give women - or men - the right to ask police about a partner's history.

A tougher option, to give an individual or their friends and family a right to demand them information from police, is thought to have been rejected.

The legislation has been named after Michael Brown's daughter Clare Wood, a 36-year-old mother strangled and set alight by a boyfriend she met on Facebook.

Mr Brown began his campaign to change the law six months ago, and has been contacted by countless women experiencing domestic abuse.

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Ministers now want women like Clare, and men, to be able to go to police to check out a partner's history.

One of the trials will be in Salford, Manchester. Local Labour MP Hazel Blears told Channel 4 News said it was "incredibly important".

Domestic violence is on the increase, with 21 men and 94 women murdered by a partner, ex-partner or lover in 2010 - more than two a week.

A Home Office spokesman said: "Domestic violence is a particularly dreadful form of abuse and we are constantly looking at ways to strengthen protection for victims.

"That is why we consulted on introducing a domestic violence disclosure scheme, often known as 'Clare's law'. We will be making a formal announcement shortly."