HUDDERSFIELD and Dewsbury police divisions are set to merge.
The new division will be known as Kirklees Police from next April and will be one of the biggest in the country per head of population.
The police say the merger will mean that more money will be available for extra officers and support staff.
Savings are expected to be made from cutting the number of senior management posts in both divisions.
But Huddersfield MP Barry Sheerman and other politicians have major worries about the move. Mr Sheerman - who is to raise the issue with Home Secretary David Blunkett as a matter of urgency - said: "I am very concerned about this. There has been a lack of consultation.
"I have tried, but ultimately failed, to talk to the senior police management about this proposal. I am very dismayed that myself and other local MPs have been left out of the discussions on such a major change to policing.
"It is our role to represent the interests of the population," he added.
"There has been a very poor level of debate and discussion. The least we could have expected was a dialogue."
Mr Sheerman added: "The people I have talked to are very concerned that north Kirklees and south Kirklees are very different communities. The policing needs to be different in these two areas.
"It would be very unwise to treat both as the same. It could lead to very serious problems that we could pay very dearly for in the future."
He said: "Even at this late stage I would like to talk to the chief constable. I will also be asking to talk to Mr Blunkett before any change takes place."
The merger decision was made at a special private meeting of West Yorkshire Police Authority on Wednesday.
It has recommended that its best value review committee rubber-stamp the decision on Friday, October 8.
A West Yorkshire Police spokeswoman said: "Assurances were given that no police stations would be closed.
"Indeed, money and posts would be made available by the changes for additional operational officers, staff and supervisors."
She added: "This was a very difficult decision, taken after long and hard debate.
"It promises stronger policing at the local level, with more resources for frontline policing. None of our communities will lose out."
A police authority spokesman said: "We are committed to seeing improvements in local responsiveness and accountability, on top of the recent reductions in crime.
"This is a change in management structure that will improve communication and co-ordination and increase the number of officers available for local policing."
But Clr Ken Smith, a Labour councillor on the authority, said he was bitterly disappointed at the merger decision.
He said he fought to dissuade police chiefs from the merger - as did another Kirklees representative, Clr Tony Woodhead - but lost.
Clr Smith added:
"Policing should be as close to the public as possible, in order to respond to people's needs."