David Cameron will announce tougher laws on stalking in England and Wales as he meets victims today, sources said.
The Prime Minister will meet stalking victims and campaigners at a Downing Street reception on International Women's Day as amendments are made to the Government's Protection of Freedoms Bill to crack down on stalkers.
Mr Cameron confirmed he wanted to look at a specific offence of stalking at Prime Minister's Questions in the Commons yesterday.
Clare Bernal who was shot dead at the Harvey Nichols store in London's Knightsbridge
The move comes after a parliamentary inquiry called for a new offence to be brought in immediately to stop harassment and intimidation turning to murder.
But MPs and peers from all parties warned that a new law alone would not be enough to protect victims and that "fundamental reform" of the system was needed.
Plaid Cymru parliamentary leader Elfyn Llwyd, the inquiry's chairman, said: "The Prime Minister's invitation to Number 10 signals a promising development that will hopefully result in a change to the current inadequate law.
Clifford Mills was found guilty of murdering Lorna Smith (pictured)
"Despite not receiving any concrete assurances yet, the Prime Minister's commitment to this issue is clear and I'm quietly confident. I find it hard to imagine that he would invite us all to Downing Street just to slap us down."
Laura Richards, a psychologist who was an adviser to the inquiry, also welcomed the moves saying that victims were being repeatedly let down by criminal justice agencies in a "scandal that cannot continue".
It follows a year-long campaign by the charity Protection Against Stalking and the probation union Napo.
Harry Fletcher, Napo's assistant general secretary, said: "It is essential that any new legislation ensures that victims are properly protected and perpetrators receive adequate sentences and attend programmes that combat their obsessive behaviour."
Mr Fletcher, also an adviser to the inquiry, said the Government's proposals would be examined in detail to ensure they will effectively deal with the problems of the current system.
Campaigners have warned that anything less than a specific law on stalking might fall short of solving the problems with the current system.
Changing the laws on harassment to create an offence of putting someone in fear of violence would always be hard to prove in court, leading to stalkers being convicted of lesser offences and being back on the streets quicker, they warned.
Some 120,000 victims, mostly women, are stalked each year but just 53,000 are recorded as crimes by police and only one in 50 of these lead to an offender being jailed, the inquiry heard.
Just 20 stalkers a year are jailed for longer than 12 months for putting a victim in fear of violence, while some were behind bars for just days and others were sentenced to community orders and "inappropriate" domestic violence courses, campaigners said.
The calls for reform came as a man who stalked his ex-girlfriend on Facebook before stabbing her to death was jailed for life with a minimum term of 21 years after being found guilty of murder.
Clifford Mills, 49, attacked Lorna Smith after inviting her to his flat in Brixton, south London in February last year. He denied murder, claiming he was suffering mental abnormality at the time, but an Old Bailey jury took just 90 minutes to find him guilty last month.
Another stalking victim, Claire Waxman, 35, was awarded £3,500 damages after the High Court ruled the state failed to protect her when charges against her stalker were dropped.
Ms Waxman, who runs a business in Willesden Green, north-west London, complained of "serious and persistent" harassment over eight years by freelance television producer Elliot Fogel, 36.
Lord Justice Moore-Bick said Ms Waxman was entitled to damages in respect of the "alarm and distress caused by the failure of the CPS to pursue the prosecution".
He said: "The state owed her a duty to take proper measures to protect her and was in breach of its duty in failing to pursue the prosecution."
Ms Waxman is expected at today's reception along with Tricia Bernal whose daughter Clare was shot and killed by her obsessive ex-boyfriend in the Harvey Nichols shop in Knightsbridge, London in 2005.
Michael Pech, 30, was awaiting sentencing after admitting harassing Ms Bernal, 22, when he killed her. He then turned the gun on himself.
Click to read David Cameron's blog How We're Tackling Violence Against Women: An Iceberg Under the Surface of Society.