The Home Secretary, Michael Howard, was asked to ensure that a Private Member's Bill from the Labour MP Janet Anderson goes through unopposed when it comes up for a Second Reading on Friday.
The Labour Home affairs spokesman Jack Straw said: "There is a clear need to legislate on stalking.
"The Bill will provide an ideal vehicle to get provision on the Statute Book before the summer recess. Further delay will only mean further misery for thousands of people."
But the Home Office minister David MacLean said although the Government shared the concerns about stalkers, he had reservations about the Bill.
"I fully understand and sympathise with what Janet Anderson is trying to achieve," he said. "I am always prepared to consider any proposals to give further protection to innocent people whose lives are being made a misery by the evil actions of others.
"However, the Government has some concerns about the Bill. Its scope could be too wide. It could criminalise legitimate activities.
"For example, journalists door-stepping a politician in hot pursuit of tomorrow's front page story could find themselves falling foul of the laws."
He said the Home Office was conducting a review to see what new measures might be introduced and that existing laws deal with the worst cases.
He added: "Legislation must be effective."
A Home Office spokeswoman said: "We have a number of reservations at this stage. We are looking at it but as we understand it, is too wide."
Ms Anderson's Bill has been drafted following talks with the Lord Chancellor, senior Home Office officials - at the invitation of Mr MacLean - the Police Federation, the Suzy Lamplugh Trust and police officers.
A key factor is the proposal to introduce prohibition orders, which would allow magistrates to jail any stalkers breaching them.
A spokeswoman for the Suzy Lamplugh Trust said it was nonsense to make a comparison with journalists' activities.
"Stalking is something which goes on for months and months and is crystal clear," she said.
"The Government has given help in drafting the Bill through Home Office Civil servants. Why has it gone so horribly wrong?
"These reservations could be an unnecessary delay to something which everyone accepts is needed."