People who are not registered to vote should not expect to get state pensions and other benefits, says a Labour MP.

Siobhain McDonagh wants to bring in a bill that would make access to public services dependent on being on the electoral roll.

She said it would restore millions to the electoral register at a stroke and "ensure they engage" in democracy.

The Electoral Commission estimates that at least 6m people were not registered to vote in Britain in December 2010.

Introducing her Ten Minute Rule bill in the Commons, Mitcham and Morden MP Ms McDonagh said: "Registering to vote is just about the nearest thing that this country has to a social contract. It's a recognition that we live in a democracy and we abide by the rules of that democracy.

'Great concern'

Quoting figures from just before the 2010 general election, suggesting 3.5m people were not registered to vote, she said it was mostly the young, disadvantaged, private rental tenants, ethnic minorities or disabled people.

If you don't like living in a democracy, fine, but don't expect all the good things that democracy offers in return Siobhain McDonagh, Labour MP

"Their disengagement from democracy is a cause of great concern to me and to many members," she said.

"This bill will ensure they engage. In future, if someone wants housing benefit, a state pension, a National Insurance number, or even a driving licence - they will have to be on the electoral register. I don't think that's too much to ask, after all, if you need to be on the electoral register to get a credit card, why not to get a driving licence?"

The MP said linking being on the electoral roll to public services would "draw an explicit connection between democracy and the benefits we enjoy because we live in a democracy".

"If you don't like living in a democracy, fine, but don't expect all the good things that democracy offers in return," she said.

Underclass 'institutionalised'

Ms McDonagh is concerned that the move to a system of individual voter registration across the UK in 2014 - which the government says will combat electoral fraud - will mean many more people failing to register to vote at all.

At the moment, people are registered by household with the head of a household responsible for ensuring all eligible voters are included.

But, in future, everyone will be expected to register individually, providing identification such as their National Insurance number.

"Mums and dads are about to be prevented from registering their children to vote," she said.

Estimates suggested about a third of eligible voters would not register - and the impact would be worse in poor areas, she said.

"What we will see if we are not careful is the people on the edges of society will slowly disengage, we will institutionalise the underclass."

Registering to vote should be "stage one in the process of interacting with the government", she said.

"The bill is about living in a something-for-something society, public services in return for a civic duty."

Her bill - a type of private members' bill - passed its first Commons hurdle without opposition and is scheduled for a second reading on 24 January 2014. These types of bill have no chance of becoming law unless the government adopts them.

Councils are beginning a rehearsal of the new system which comes into force in England and Wales next June and in Scotland in September 2014, following the independence referendum.

Ministers say two-thirds of people already on the register will not have to do anything because the current register will be matched against other public databases such as that held by the Department of Work and Pensions.

Those people whose records do not match will be asked to register using the new form.

The government launched a campaign to try to get more people to register to vote earlier this month. It targets those with historically low levels of registration, including under-24-year-olds, social tenants and hard-to-reach groups, such as students.