David Cameron is "interested" in exploring the idea of varying welfare payments across the UK to reflect differences in wages and the cost of living, Downing St has said, in a move likely to draw more anger at Tory proposals to introduce radical reforms to the social security system.

The prime minister's official spokesman said on Monday that "clearly wage rates vary around the country".

"What someone receives in benefits compared to what they potentially get by going into a job has an impact on the incentives they face."

The implicit suggestion is that in areas of Britain where wages and the cost of living are lower, having the same benefit payouts as more affluent areas could act as a disincentive to come off benefits and get a job.

Although the idea remains just that, it's another sign that the Tories are considering standing at the next election with radical proposals to change the welfare state. On Monday David Cameron confirmed he was looking at plans to curb housing benefit for under 25s.

The PM said: "There are many who will have a parental home and somewhere to stay – they just want more independence.

"The point is this: the system we inherited encourages them to grab that independence, rather than earn it. Perversely, the benefits system encourages this process from one generation to the next."

An early draft of Cameron's speech on Monday included the idea of regional variations in welfare payouts, but this was dropped from the final text at the last minute. Despite this, Downing Street has confirmed it is still on Cameron's radar as a possible future policy.

The government is hazy on whether any changes to the welfare system would happen before the next general election. Number 10 says the ideas are likely to be included in the next spending review - expected next year.

Ministers are said to be cooling off the idea of introducing regional or local pay variations for civil servants and other public sector workers. Although George Osborne floated the idea in the Autumn Statement last year, signals from Whitehall in recent weeks suggest the changes would be too politically damaging for the coalition because many Lib Dems, particularly in places like Cornwall, fiercely oppose them.

Many believe that any form of regionalisation - whether for benefits, public sector wages or anything funded for by the taxpayer - is impossible because standards of living can vary hugely within a region. Tories in the north of England always worry how it would play out on their constituencies, others see it is risking an extension of the north-south divide.

But the government has indicated that it will need to slash the welfare bill by a further £10bn in order to meet its deficit reduction timetable - and Cameron's speech on Monday is seen as a way of outlining other ways in which the government could achieve that target.

In 2007 a form of public sector regionalisation was introduced for the Courts Service, with staff salaries being lumped into different zones. It led to a patchy map of Britain, with places like Manchester and Portsmouth put in the same pay zone. But attempts to widen this scheme to other parts of the public sector appear to be foundering, partly because Lib Dems are fiercely opposed.

At the moment Downing Street says these are Tory ideas, not coalition ones, in a sign that the two governing parties are already seeking to carve out distinct policy agendas ahead of the next election, scheduled for May 2015.

A Lib Dem spokesman said: "This is a speech by David Cameron as leader of the Conservatives floating ideas for the next election. He has every right to do that but it's not Coalition policy.

"Where we do agree is the the core principle of the Coalition's welfare plans - making work pay. Liberal Democrats want to ensure we have a system which, as well as being affordable, protects the vulnerable and gives a helping hand to those who are struggling to find work."

Cameron also signalled on Monday further curbs on Income Support for lone parents, saying: "We also need to ask if single parents living on benefits can do more to prepare for work. Today, we have 580,000 lone parents on out-of-work Income Support.

"Before this Government came to office, single parents weren’t required to look for work until their youngest child was seven years old – up to three years after they’ve started primary school. We thought that needed changing – so we’re bringing it down to five years-old, about the age they start school.

"But now there is free childcare for all children from age three, that does prompt a question about how some of that time, 15 hours a week, more than a thousand hours over a couple of years, should be used by parents on Income Support."

The ideas have been widely attacked, with some claiming the government is making life harder for young people while refusing to introduce means-tested benefits for pensioners.

Some people brand the Tories' welfare plans a cynical calculation because older people are more likely to vote. At the last election nearly three-quarters of pensioners turned out at polling stations, while fewer than 40% of people under 30 bothered to vote.

Shadow Work and Pensions Secretary Liam Byrne called it "a hazy and half-baked plan," saying: " "Many young families with their first foot on the career ladder will be knocked off if help with their rent is taken away. And young families that want to work won't be able to move where the jobs are."

"The way to get the spiralling benefits bill down is start getting young people and young families back to work," Byrne added.

Loading Slideshow...
  • Security staff lead in the fans for the start of day 1 of the 2012 Wimbledon Championships. (Photo credit: PA)

  • The order of play board is prepared before the start of day one of the 2012 Wimbledon Championships at the All England Lawn Tennis Club, Wimbledon. (Photo credit: PA)

  • Kenny Riedmann, right, collides with Fernando Amantini during an AMA SportBike motorcycle race at the Barber Motorsports Park in Birmingham, Ala., Sunday, June 24, 2012, as part of the Triumph SuperBike Classic. (AP Photo/The Birmingham News, Mark Almond)

  • Victor Ortiz, right, takes a punch from Josesito Lopez during the ninth round of a WBC welterweight boxing match in Los Angeles, Saturday, June 23, 2012. (AP Photo/Jae C. Hong)

  • Euro 2012 England Italy - England's Wayne Rooney reacts after losing the penalty shootout of the Euro 2012 soccer championship quarterfinal match between England and Italy in Kiev, Ukraine, Monday, June 25, 2012. (AP Photo/Michael Sohn)

  • US Diving Trials -Gracia Leydon-Mahoney competes in the women's 10-meter platform final at the U.S. Olympic diving trials, Sunday, June 24, 2012, in Federal Way, Wash. (AP Photo/Elaine Thompson)

  • Mexico Elections-A student of the #YoSoy132 or "I am 132" movement demonstrates in Mexico City, Sunday, June 24, 2012. #YoSoy132 is the name of a university movement that rejects the possible return of the old ruling Institutional Revolutionary Party (PRI) ahead of Mexico's July 1 presidential election. (AP Photo/Marco Ugarte)

  • A Bengal Tiger named Akasha dives into the water after a piece of meat at Six Flags Discovery Kingdom on June 20, 2012 in Vallejo, California. On the first day of summer, temperatures in the San Francisco Bay Area ranged from the mid seventies by the coast to mid nineties inland. (Photo by Justin Sullivan/Getty Images)

  • Red Hot Chilli Peppers Perform At Sunderland's Stadium Of light -Flea of Red Hot Chilli Peppers performs on stage at Stadium of Light on June 24, 2012 in Sunderland, United Kingdom. (Photo by Marc Marnie/Redferns via Getty Images)

  • Fires Rage in Colorado -A deer jumps through a fence along U.S. Highway 24 while escaping the Waldo Canyon Fire Sunday, June 24, 2012. Photo by Christian Murdock/Colorado Springs Gazette/MCT/ABACAPRESS.COM

  • Gay Pride -Niki Ryan, left, applies lipstick for her niece Brenna Ryan as they wait for the start of San Francisco's 42nd annual gay pride parade on Sunday, June 24, 2012. San Francisco's annual Gay Pride celebration kicks into high gear Sunday when the streets of downtown are expected to be jammed with revelers for the annual parade. Organizers say more than 200 floats, vehicles and groups of marchers will take part in the parade. (AP Photo/Noah Berger)

  • Philippines Festival - A Filipino Catholic devotee, who soaked himself in mud and wrapped in mostly banana leaves, walks around a village to beg for candles prior to attending a mass to celebrate the Feast of Saint John The Baptist at Bibiclat village, Aliaga township, Nueva Ecija province in northern Philippines, Sunday, June 24, 2012. Traditionally the Feast of St. John The Baptist is celebrated in this predominantly Roman Catholic nation in Asia by dousing unwary people with water but in this sleepy village of Bibiclat, the residents soak themselves in muddy rice fields and don banana leaves instead. The unique celebration now became a tourist attraction. (AP Photo/Bullit Marquez)

  • A Rebekah Brooks impersonator is pictured in the stocks, outside the London Dungeon. The London Dungeon asked 500 visitors to its 17th Century Courtroom last week. They were asked to choose from three defendants placed in the dock by the DungeonÂÂ's resident Judge Farquar - controversial ex News International boss, Rebekah Brooks, Chancellor George Osborne and Comedian Jimmy Carr. Brooks polled the most votes and passersbys, along with Judge Farquar, were invited to pelt ÂÂ"BrooksÂÂ" with a selection of rotten fruit, vegetables and eggs. Monday, June 25, 2012. (AP Photo/Jonathan Short)